Other investigators, he said, were seeking surveillance images, gathering fuel records and checking the helicopter's history.
The investigators, officials said, also were checking on the source of funds used by the company to expand.
The guard said investigators were checking a videotape taken right before the bombing to identify the bomber.
Leaning over him to look at the other side of the man's uniform, the investigator checked for a name.
Last night, investigators were checking to see if a car they had recovered near the shooting had been used in the attack, the police said.
He did not know how long it would take investigators to check the device.
The investigators are checking the cargo to determine what was loaded on the aircraft.
They said one federal investigator had checked with the criminal division of the Justice Department, which said there was no such order.
Under the agreement reached by party leaders on Wednesday, each member of Parliament will be able to ask investigators to check his or her background.
Now, investigators will check criminal and immigration histories, at the beginning of a refugee's application process, rather than at the end.