The House Republican staffer arrested Friday after carrying a firearm into a congressional office building had a semi­automatic 9mm Smith & Wesson handgun and an ammunition magazine containing nine hollow-point bullets, according to court documents made public Saturday.

D.C. Superior Court Judge Gerald I. Fisher ordered Ryan Lee Shucard, press secretary for Rep. Tom Marino (Pa.), released from custody pending a preliminary hearing Aug. 7. The 26-year-old Alexandria resident is charged with a single count of possessing a gun outside a home or office, a felony.

Marino, whose 10th Congressional District includes areas north of Scranton, said in a statement that Shucard has been placed on indefinite unpaid administrative leave.

Shucard was arrested about 9:15 a.m. Friday as he went through security screening. The court documents, providing the first detailed account of the arrest, say Shucard put a bag on the X-ray belt at the Cannon House Office Building. A U.S. Capitol Police officer spotted the ammunition magazine, halted screening and detained Shucard, according to the documents filed in D.C. Superior Court.

Police said they found the black handgun, which was unloaded, when they searched the bag by hand. Marino’s chief of staff, Bill Tighe, said Friday that police indicated that Shucard appeared to have accidentally brought the weapon with him to work.

Shucard’s attorney, Jason Kalafat, said Saturday that his client made an honest mistake. “Everything points to this being completely inadvertent,” he said. “Ryan didn’t intend to bring a gun into the office building.”

Kalafat declined to comment further and would not say why Shucard has a weapon. He said his client’s family came to Washington to support him and “we expect to resolve this in a fair and just way.”

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