The man charged in last week's shooting of a security guard at the Family Research Council's downtown D.C. headquarters was formally indicted Wednesday, authorities said.

Floyd Lee Corkins II, of Herndon, has been charged with interstate transportation of a firearm and ammunition, a federal offense, as well as assault with intent to kill while armed and possession of a firearm during a crime of violence, both local offenses. He was indicted by a grand jury on those charges Wednesday in the District.

He faces a maximum of 55 years in prison if convicted on all charges.

Corkins, 28, is accused of entering the offices of the Family Research Council, a conservative Christian group known for its anti-abortion and anti-gay marriage stance, and allegedly shooting a security guard in the arm on Aug. 15.

Court documents indicate that Corkins might have taken issue with the FRC's opposition to gay marriage.

Corkins will appear in court Friday for an arraignment and detention hearing, where he will enter a plea and a judge will determine whether he should be held in custody pending his trial.