A live stick of dynamite was accidentally left on an old plane at an airport museum for four days, a law enforcement officer at Los Angeles International Airport said Thursday.

The official, who spoke to The Associated Press on condition of anonymity because the person was not authorized to speak publicly, said workers on the tarmac found the dynamite Tuesday when they noticed the bright colors on the stick.

The stick was left behind after a Saturday training exercise for K9 officers and their dogs who work at the airport. Though live, the dynamite would have required a detonator or explosive to be set off.

Sgt. Belinda Joseph, a spokeswoman, said the object was a training aid and "there was a certain amount of TNT contained in it" but denied that it was a stick of dynamite.

She said airport police are investigating and have notified the Transportation Security Administration.

The stick was checked out from a TSA explosive storage container for training.

The stick was left in a compartment underneath the “Spirit of Seventy Six” plane, the official said. The plane was featured at the Flight Path Learning Center and Museum on the airport’s southern edge.

The plane is outside the museum and is run by volunteers and frequently hosts school groups and other visitors.

The Associated Press contributed to this report