CANBERRA, Australia - A man who lives under a Sydney flight path was shocked when a bolt from an airliner crashed through his roof, according to a news report Wednesday.

Angelo Margiotta said he thought a bomb had exploded when the stainless steel bolt, which appeared to be about 6 inches long, struck his roof in the Sydney suburb of Five Dock on Wednesday morning, Ten Network television news reported.

Margiotta called the fire brigade and a firefighter found the bolt which had smashed two roof tiles and lodged in the ceiling.

"I was too shocked to talk ... because of the noise," Margiotta told Ten. "It was very, very loud."

Australia's aviation watchdog, Civil Aviation Safety Authority, was attempting to track down the plane that lost the bolt.

"Anything that comes off an aircraft has to be explained," CASA spokesman Peter Gibson told the network.

The bolt most likely came from a Boeing 747 or 767, Ten reported.

Sydney Airport officials said no aircraft had reported mechanical problems, Ten said, which suggested the bolt wasn't in use at the time it fell from the plane, Ten said.

Officials from the airport and CASA could not be immediately contacted.