The trial for a former MetroAccess driver accused of sexually assaulting a passenger while taking her home to Bowie, Md., has been continued to July 29.

Ezra Porter, Jr., 51, was expected to face a Prince George’s County jury Tuesday, but a witness in the case was unavailable to testify, officials with the State’s Attorney’s Office said.

Porter is accused of stopping a MetroAccess paratransit vehicle on April 19, 2013 and assaulting the only passenger on board as he was taking her home from work, authorities said.

“During the transport, Porter allegedly pulled the vehicle over and threatened to harm her if she did not remove her pants,” according to a statement from the Prince George’s County State’s Attorney’s Office. “Fearing for her safety, the victim removed her pants and Porter allegedly sexually assaulted her.”

Porter then took the woman home and her family contacted the police, Metro Transit Police said last year. Officials arrested Porter shortly after the allegations.

The Southwest D.C. man was working for MV Transportation at the time of the alleged attack and had been a driver since November 2009, Metro officials said. MV Transportation was under contract to provide services for MetroAccess, which provides door-to-door transportation to those who are disabled.

Porter has not been allowed to work for MetroAccess since Metro Transit Police launched its investigation into the allegations last year.

Porter faces one count of second-degree assault and several sex offense charges, authorities said.

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