WASHINGTON: A US official says investigators are examining the possibility that someone caused the disappearance of a Malaysia Airlines jet with 239 people on board, and that it may have been “an act of piracy.”

While other theories are still being examined, the official says key evidence for “human intervention” in the plane’s disappearance is that contact with its transponder stopped about a dozen minutes before a messaging system quit.

This official says that it’s also possible the plane may have landed somewhere.

Sources familiar with the Malaysian probe earlier told Reuters that the investigation is focusing more on a suspicion of foul play, as evidence suggests it was diverted hundreds of miles off course.

An investigative source said inquiries were focusing more on the theory that someone who knew how to fly a plane deliberately diverted the flight hundreds of miles off its scheduled course from Kuala Lumpur to Beijing.

“What we can say is we are looking at sabotage, with hijack still on the cards,” said the source, a senior Malaysian police official.