The FBI is investigating two plane crashes into the World Trade Center today as a possible terrorist act, The Associated Press reported.

The FBI is investigating two plane crashes into the World Trade Center Tuesday as a possible terrorist act, The Associated Press has learned.

A senior government official, speaking on condition of anonymity, said the agency is pursuing reports that one or both of the planes were hijacked and that the crashes may have been the result of a suicide mission.

The source stressed that the reports are preliminary and officials do not know the cause of the crashes.

"It certainly doesn't look like an accident," said a second government official, also speaking on condition of anonymity.

President Bush, notified of the tragedy before a scheduled education speech in Florida, canceled the event and made plans to return to Washington. Aides said he would first issue a statement about the World Trade Center crashes