Defendant Teng Yang appeals his conviction under 21 U.S.C. § 952(a) for importation of opium into the United States. Mr. Yang pleaded guilty to the charge after the district court conducted an evi-dentiary hearing and denied his motion to suppress evidence of drugs seized at the airport after he had passed through customs. Mr. Yang expressly reserved the right to appeal the district court’s denial of his motion to suppress and now appeals that order. We affirm.
I. Background
Teng Yang (“Teng”) and his cousin Lee Pao Yang (“Lee Pao”) flew into Chicago’s O’Hare International Airport on September 7, 1999, from Laos connecting through Tokyo, Japan. Both men were booked on an American Airlines flight from O’Hare to St. Paul, Minnesota. Teng and Lee Pao are both American citizens who had traveled to Laos to attend Teng’s father’s funeral. But when they returned to the United States from Laos, their suitcases had been packed with clothes which had been soaked in an opium solution and then dried. Teng passed through customs at O’Hare without incident. His suitcase was x-rayed at the agricultural inspection area, but his luggage was not searched by hand. After leaving the customs area, Teng took his luggage and proceeded to the American Airlines terminal, less than a mile away, via the O’Hare airport tram.
His cousin was less fortunate. Lee Pao was detained randomly for an enforcement exam and the inspectors discovered some unusually stiff clothing made of sweat-pant material in his suitcase. The clothing, which had a very strong odor, chemically tested positive for opiates. Lee Pao was arrested on the scene and, following questioning by the customs officials, he admitted that he was traveling with another person. American Airlines officials confirmed that Teng was booked on the same itinerary as his cousin. The customs agents then decided to intercept Teng based on Lee Pao’s admission that they were traveling together, the fact that drugs were found in Lee Pao’s bag, and the fact that both men were traveling on the same itinerary from Laos, a drug source country, to St. Paul, a drug destination city. They did not obtain a search or arrest warrant. The customs agents requested that the baggage crew separate Teng’s baggage from the other luggage on the flight to St. Paul. The agents then proceeded to the American Airlines terminal and announced Teng’s name over the loudspeaker. When no one responded, agents proceeded to search the terminal. One of the agents, Inspector Joseph Mar-cocig, recognized Teng, as he had seen him in line at customs with Lee Pao. Teng was taken down to the tarmac where he identified his luggage. He then agreed to return to the international terminal for questioning. The agents handcuffed him pursuant to customs policy for transportation of individuals in a vehicle (“for [their] protection and his”) and returned to the international terminal. A search of his bags revealed more opium-soaked clothes.
Teng and Lee Pao were charged in an indictment with conspiracy to import opium and importing large quantities of opium. Teng and Lee Pao filed a motion to suppress the evidence seized at the airport, which the court denied after an evi-dentiary hearing. In February 2001, Teng pleaded guilty to count three of the indictment which charged him with the importation of 2,737 grams of opium. In doing so, he reserved the right to appeal the trial court’s denial ruling on his motion to suppress. The district court then sentenced him to 24 months in prison followed by three years of supervised release. He now *944 appeals the district court’s denial of his motion to suppress the evidence found in his suitcase.
II. Analysis
In reviewing a district’s court’s ruling on a motion to suppress, this court reviews questions of law
de novo
and findings of fact and reasonable inferences drawn from those findings for clear error.
United States v. Peters,
A. Extended Border Search
The Fourth Amendment protects individuals from unreasonable searches and seizures. U.S. Const., Amend IV. Generally a search is not reasonable unless the government has a warrant supported by probable cause or there must be an exception to the warrant requirement. An administrative border search has long been recognized as such an exception.
United States v. Ramsey,
O’Hare Airport is an international gateway into the United States, and incoming passengers from international ports are subject to border searches because the airport is the functional equivalent of an international border.
United States v. Johnson,
*945
In this case, Teng was routinely searched at customs and no contraband was discovered in his luggage. It was not until he traveled to a different terminal that other circumstances caused customs agents to develop suspicion that he might be smuggling drugs into the country. Teng argues that because the search that revealed the contraband did not occur at customs, it was not a constitutionally permissible border search. His argument is that once a traveler has passed through customs, left the international terminal, proceeded to a separate terminal in the airport and checked his bags onto another flight, the opportunity for a “routine” border search has passed. The government contends, on appeal, that even though Teng had passed through customs, the search should still be described as a routine border search, relying on
United States v. Ramos,
The district court held that this search was not a routine border search, but was justified under the extended border doctrine, a doctrine our own circuit has not examined or applied.
United States v. Odland,
*946
The constitutional concern of extending the border in this manner is that it potentially permits searches with less than probable cause at significant distances from our national borders. For example in
Caicedo-Guamizo,
a suspect was searched in Los Angeles after he had passed through customs in New Orleans and changed flights en route in Houston. The court allowed a search in that case under the extended border doctrine, even though several hours and over a thousand miles had passed since his border crossing.
Caicedo-Guarnizo,
Finally, the use of the extended border doctrine allows this circuit to more effectively analyze the reasonableness of non-routine border searches that occur near the border. Previously, in a case concluding that a border search was routine, this circuit observed that non-routine border searches need at least be supported by reasonable suspicion.
See Johnson,
It is the enforcement of the customs laws combined with the mandate of protecting the borders of the United States that permits the extension of the search rights of border authorities to allow non-routine searches in areas near our nation’s borders. Because the extended border doctrine strikes a sensible balance between these two interests we conclude that it is a valid legal standard applicable in this circuit. Thus, we now consider the relevant factors under this standard for determining the constitutionality of this search.
1. Reasonable certainty of a border crossing.
First, we ask whether there is a reasonable certainty that a border has been crossed. “Reasonable certainty is a standard which requires more than probable cause, but less than proof beyond a reasonable doubt.”
See Cardenas,
2. Reasonable certainty of no change in condition of his luggage.
Next, we must determine whether there was a reasonable certainty that no change in the condition of the luggage occurred since the border crossing. Again, neither party disputes this element. Teng claims he carried his own bags, via the O’Hare airport tram, to the American Airlines terminal. At the terminal, he waited in line at the gate and checked his own bags. 3 Airport personnel then removed his bags from the plane, where they were identified by Teng. Teng does not contest this factor and does not allege any circumstances in his affidavit where his luggage would have changed condition. While neither party disputes this element, it is this factor that establishes the proper nexus with the border to allow a search and so we will examine it accordingly.
Other circuits have considered the totality of the circumstances in determining
*948
whether officers had a reasonable certainty that any contraband discovered in a search was in the possession of the suspect at the time the suspect crossed the border.
See United States v. Alfonso,
At some point a subject’s relationship with the border becomes so attenuated that customs officials lose the right to detain him without a warrant.
See Caicedo-Guarnizo,
3. Reasonable suspicion of criminal activity.
Last, we examine whether customs inspectors had reasonable suspicion that Teng was involved in criminal activity. Teng contends that the only reason that he was stopped and his luggage was searched was that his traveling companion was caught with drugs, and that this is not enough to create a reasonable suspicion that he was involved in criminal activity. The government responds that in addition to drugs being found in Lee Pao’s bag, both were traveling on the exact same itinerary from Laos, a drug source nation, to St. Paul, Minnesota, a known opium destination, and that Teng failed to respond when his name was called on the speakers. After considering the evidence presented in the evidentiary hearing, the district court concluded that a reasonable suspicion existed to detain Teng and search his bags. 4
*949
This final factor in the “extended border search” doctrine is analogous to a
Terry
stop.
See United States v. Lopez-Gonzalez,
The suspicion justifying a search of this type must be “based on objective factors and judged in light of the experience of the customs agents.”
United States v. Dorsey,
Therefore, under the extended border search doctrine, we conclude that the search of Teng was reasonable under the Fourth Amendment. Officers had a reasonable certainty that Teng had crossed the border and that his luggage had not changed in condition, and they had a reasonable suspicion that criminal activity was occurring.
B. Search Incident To An Arrest
We now turn to Teng’s alternative argument, that the evidence should be excluded because it was obtained in a search incident to an unlawful arrest. The district court concluded that Teng was not under arrest when he was handcuffed and returned to the international terminal. Teng argues that he was arrested without probable cause prior to the search of his luggage and therefore the evidence recovered from his luggage should be suppressed as the fruit of an unlawful arrest. Generally, when police actions create a situation that exceeds a short detainment, a stop becomes an arrest which requires probable cause that the person is commit
*950
ting or has committed a crime.
Beck v. Ohio,
Nevertheless, we would agree with the district court’s analysis. The detention of Teng was necessary and limited in scope and duration, and the handcuffing and transportation of Teng back to the international terminal did not convert the stop into an arrest. This case is different from our previous case law in this area,
see, e.g., United States v. Glenna,
III. Conclusion
The search of Teng’s luggage was reasonable under the extended border search doctrine. The agents had a reason able certainty that he had crossed the border and that his luggage had not changed condition, and they had a reasonable suspicion that criminal activity was occurring. In addition, because Teng was not arrested prior to the search, it was not a search incident to an unlawful arrest. For these reasons, we affirm the district court.
Notes
. While this case does not involve issues of national security that might be implicated by terrorist activities, the events of September 11, 2001, only emphasize the heightened need to conduct searches at this nation’s international airports. "[A]ttempts to counter foreign threats to the national security require the utmost stealth, speed and secrecy.”
United States v. Truong Dinh Hung,
.
Customs agents have the statutory authority to conduct searches pursuant to 19 U.S.C. § 482. The statute allows searches of individuals "wherever found” with reasonable cause to believe that the suspect has items that were imported into the country "contrary to law.”
Id.
The phrase "wherever found” is not infinite in scope but has been interpreted to be limited by Fourth Amendment reasonableness constraints.
See Bilir,
. Typically, once a passenger leaves customs at O’Hare there is an opportunity within the international terminal to immediately check luggage with any connecting airlines. If Teng had taken advantage of the immediate check-in area then there would be little doubt that his luggage was in the same condition when it was searched by the agents as it was when it crossed the border because it would have been out of his control. The agents were not aware at the time that his luggage was pulled from the plane whether he had checked his own bags at the American Airlines terminal or the international terminal. It is also unclear whether or not they could have learned this information from Teng due to his limited ability to speak English.
. The district court did not specifically mention in its ruling that Teng's failure to respond to the page at the American Airlines terminal contributed to the suspicion of the officers. Also, the court did not mention that when he spotted Teng, the inspector noticed Teng was "kind of hunched over and trying to stay out of sight.” However, this information was disclosed during the direct examination of Inspector Joseph Marcocig during the evi-dentiary hearing on the motion to suppress. Inspector Marcocig was subsequently cross-examined by Teng’s attorney. Even if the district court did not mention these facts, this court may consider them in examining the totality of the circumstances that led to stopping Teng.
See United States v. Brown,
