Authorities withheld information about a potentially lethal security failure involving a pipe bomb at Edmonton International Airport, CBC News has learned.

Sources have told CBC that Garda, the private company hired to conduct screening at the airport, told its employees for months there was no pipe bomb incident, despite the fact an explosive device had been seized from a teenager on Sept. 20, 2013.

Garda declined an interview request from CBC.

Garda has been contracted by the Canadian Air Transport Security Authority (CATSA) to provide security services at the Edmonton airport. Earlier this month, CATSA distributed a memo to employees saying that an explosive device had been seized and a person charged, but it did not specify at which airport the incident occurred.

“The incident highlights why your role in providing effective security screening is critical,” states the memo.

Skylar Murphy, 18, of Spruce Grove, Alta., was allowed to board a flight to Mexico on Sept. 20, 2013, with his family because screening personnel did not recognize the pipe bomb he had in a camera bag was an explosive device. The incident was not reported to the RCMP until Sept. 24. Murphy was arrested by the RCMP when he returned from Mexico on Sept. 27.

The teenager was charged with possession of an explosive substance.

RCMP's role in incident

The RCMP also withheld information from the public about the pipe bomb incident.

The force issued a news release announcing the charge against Murphy on Oct. 1, 2013, but the three-sentence release made no reference to the fact that the charge related to the Edmonton International Airport, or that Murphy had carried a fully functioning pipe bomb into the security screening area.

CBC News has also now learned that at least three Garda employees handled the pipe bomb – a steel pipe with two caps on the end with a nearly three-metre long fuse wrapped around it – but none of them realized it was a bomb. A Garda supervisor was on site at the time.

Pipe bomb posed danger

Sources have also told CBC News the pipe bomb posed a danger to anyone in close proximity. Despite this, it was deposited into a “forfeit” bin along with other seized items such as scissors and toothpaste. It was then moved to an office, where it sat for four days before a CATSA official saw it and immediately notified the RCMP.

The pipe bomb was first discovered when Murphy's bag was X-rayed. Sources say protocol was not followed when the bag was removed from the machine. An alarm button should immediately have been pressed, which would have brought an RCMP officer to the scanner.

One source with direct knowledge of the incident said that had the RCMP been notified, as prescribed by protocol, the device would have been left in the machine, the area would have immediately been evacuated, and a bomb squad would have been called in.

'A bomb is always unstable'

“A bomb is always unstable,” said the source, who spoke on condition of anonymity. "You don’t know when it is going to blow up. You don’t know what it is going to take to blow it up. It is very dangerous.”

The source also said Murphy should have been immediately arrested and any of his checked baggage should have been pulled from the flight.

Mathieu Laroque, a CATSA spokesman, told CBC News that security staff breached protocol when they did not push the alarm to notify the RCMP. He said staff should have recognized it was a potentially dangerous device, called in the RCMP and cordoned off the area.

Laroque also reiterated that several staff members were disciplined, some with suspensions.

Murphy pleaded guilty to possession of an explosive device in December and was given a one-year suspended sentence, a $100 fine, and ordered to make a $500 donation to a burn unit.