Federal investigators say the driver in last year’s deadly bus crash in the Bronx may not have had the sleep he claimed in the days leading up to the accident.

Newly-released documents from the National Transportation Safety Board show Ophadell Williams’ cell phone and rental car were used heavily during hours he said he was sleeping.

The documents also show Williams’ driving privileges were suspended 18 times between 1987 and 2007.

Williams was driving a busload of passengers back to Manhattan after a night of gambling last March when his bus flipped on its side on the New England Thruway.

Fifteen people were killed.

Williams told investigators a truck clipped the bus.

He pleaded not guilty to charges of manslaughter and criminally negligent homicide.

The NTSB will hold a meeting on the crash in Washington next month.

(Source: NY1)