By Dave Warner

PHILADELPHIA (Reuters) - A man avenging his girlfriend over a questionable Facebook photograph was charged on Friday with falsely reporting explosives aboard a plane that was ordered to return to Philadelphia Airport, authorities said.

Kenneth Smith Jr., 26, was charged with using a telephone to convey false information about the woman's former boyfriend, who was a passenger aboard the US Airways flight from Philadelphia to Dallas on Thursday.

Shortly after the plane had departed, it was ordered back to Philadelphia when police received a call that the former boyfriend, Christopher Shell, 29, was carrying explosives on board.

No dangerous materials were found and the incident was soon deemed to be a hoax, authorities said.

"Smith stated that his motive for doing so was to avenge Person 1's (Shell) ex-girlfriend of whom Person 1 had posted a compromising picture on Facebook," said an FBI affidavit.

Smith, who lives in Philadelphia, could face a maximum of 10 years in prison and a fine of up to $250,000 and possible restitution, said the Patricia Hartman, spokeswoman for the U.S. Attorney's Office.

While not charged in plane incident, Shell was arrested when he finally arrived in Dallas on an outstanding warrant of marijuana possession.

Shell, who now lives in Philadelphia and turned 29 on Thursday, was taken off the plane for questioning, but once cleared was allowed to fly to Dallas on a later plane.

(Reporting by Dave Warner; Editing by Barbara Goldberg and Leslie Gevirtz)