Image caption Mr Hersey had been drinking before the flight, a witness said

A US man accused of trying to open an emergency exit door during a Florida to Boston flight has denied a charge of interfering with a plane's operation.

Prosecutors said Robert Hersey, 43, of Arlington, Massachusetts, had tampered with the door, triggering an alarm.

An off-duty police officer sat with him for the rest of the Delta flight, a spokeswoman for the airline said. Witnesses described him as drunk.

Mr Hersey's lawyer said he accidentally touched the cover for the door.

The cover fell off and his client replaced it, US media quoted lawyer Ron Wayland as saying, causing a light to go off and leading the pilot to ask Mr Hersey to change seats.

Mr Wayland described the incident as a "non-event", adding that his client had not been drunk.

Mr Hersey was charged on Tuesday night with interfering with the operation of an aircraft.

Passengers told local media that Mr Hersey, who was wearing a shirt supporting the Boston Bruins hockey team, was foul-mouthed, intoxicated and unhappy the flight was late.

He tried to open the exit door on the Airbus 320 about half-way between Orlando, in Florida, and Boston, Massachusetts, passengers told the Boston Globe.

Bail was set at $1,000 (£600) by the court in Boston.