Dutch investigators said Tuesday they found no evidence that a Nigerian suspected of trying to blow up a U.S.-bound airliner contacted accomplices at Amsterdam's airport, and that he already had the explosives on him when he arrived on a connecting flight.
Umar Farouk Abdulmutallab flew to Schiphol Airport from Lagos, Nigeria, before boarding a Northwest Airlines flight to Detroit on Christmas Day. He allegedly tried to blow up the plane by injecting chemicals into a package of pentrite explosive concealed in his underwear.
The failed attack caused popping sounds and flames that passengers and crew rushed to extinguish. Abdulmutallab is in U.S. custody charged with trying to blow up the Northwest flight.
Investigators checking more than 200 hours of security camera footage from Schiphol's shopping mall in the transfer area and departure gate say Abdulmutallab underwent a security interview and check and did nothing unusual in his three-hour stopover. Earlier, authorities said the suspect went through a routine baggage check and scan by a metal detector before boarding.
"Investigations so far have uncovered no indication that the suspect contacted possible accomplices at Schiphol, left the transfer area or behaved suspiciously," the National Prosecutor's Office said.
Abdulmutallab has told U.S. investigators he received training and instructions from al-Qaida operatives in Yemen.
As well as studying video footage, investigators have seized the airline seat Abdulmutallab occupied from Lagos to Amsterdam and sent it for forensic tests to check for traces of explosives.
They also are interviewing passengers and crew on the Lagos-Amsterdam flight and ground staff ranging from security officers to check-in staff and cleaners at Schiphol.
Dutch authorities have stepped up security on all flights from Schiphol to the U.S. since the attack, including using full-body scanners that might have detected Abdulmutallab's explosives.