A popular downtown nightclub was shut down temporarily by D.C. Police Chief Cathy L. Lanier after an assault there that police allege club employees tried to cover up, officials said.

In a letter to the city’s Alcoholic Beverage Regulation Administration, Lanier said a man was struck on the head with an unknown object at the club, the Park at Fourteenth, on 14th Street NW. Lanier said the victim, who was intoxicated, had bumped repeatedly into the person who hit him.

The attack occurred in a third-floor restroom about 2:40 a.m. Sunday, and the victim also hit his head on a door, police said. The victim, who was not named, suffered a head injury, police said.

The nightclub staff bandaged the victim’s head and escorted him out the back door “in a deliberate attempt to avoid being detected” by D.C. police officers, who were working at the front of the building, Lanier wrote. The nightclub staff also cleaned up the scene and failed to call 911 or notify police, she said.

In November, the club’s owner, Marc Barnes, was charged with misdemeanors after allegedly shredding identification that he said was used to fraudulently enter the club. Prosecutors later dropped the charges.

Makan Shirafkan, an attorney for the Park, said that Sunday’s incident occurred in the club but that Barnes and the staff cooperated with police. He also said that the victim refused the staff’s help before leaving on his own and that Barnes brought investigators into the club to view surveillance camera footage.

“Unfortunately it seems the chief’s office is doing these without doing the proper investigation,” Shirafkan said.

The closure began at 7:30 p.m. Sunday and will last at least 96 hours. The Alcohol Beverage Control Board will consider whether further sanctions are warranted.