Bomb note found on plane forces emergency landing

MIAMI, Florida (CNN) -- An American Airlines flight out of Florida made an emergency landing Thursday night after a written bomb threat was found in a bathroom, officials said.

American Airlines Flight 1640 was en route from Miami to Boston, Massachusetts, according to a Transportation Security Administration statement.

The note was found shortly after takeoff, forcing its return to Miami International Airport about 45 minutes into the flight, the TSA said.

All 168 passengers and six crew members were evacuated and federal authorities were investigating.

A sweep of the plane revealed no suspicious items, and the flight was rescheduled for Friday.

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