A resident in a townhouse neighboring City Hall was unloading his groceries one August evening when a beer bottle hurled past him and shattered on the ground.

That same night, a whisky bottle was flung from behind the residence hall, smashing a window at the adjacent Circle Arms Apartments.

The incidents are among five cases over the past year in which bottles thrown from City Hall’s balconies landed on a neighboring street, roof or yard, prompting the University Police Department to install three surveillance cameras to keep an eye on the building’s terraces.

“It is a huge concern for me because of the potential for injuries to humans,” University Police Department Chief Kevin Hay said. “I don’t know why [it is] happening. Why does anyone commit an act of vandalism or throw a bottle where they might hit someone on a dark evening?”

Mounted in the back of City Hall near its pool and courtyard, the new cameras point upward to capture shots of the balconies. Although just five incidents of bottle tossing have been reported in the past 12 months, Hay’s department is “fairly certain there have been more” and have found bottles lying on nearby rooftops.

The newly installed cameras, which came from the old University Parking Garage, will help UPD find, identify and prosecute the vandals and hopefully deter future incidents, Hay said.

Hay believes alcohol use is associated with the cases.

“If this was carelessness with a bottle that was knocked inadvertently off a rail or another part of a balcony, then it would land in a pool. These bottles are being thrown,” Hay said. “Throwing a bottle off a balcony at two in the morning where you might hit someone’s car…is an act of belligerence.”

Metropolitan Police Department officers, aware of neighbors’ grievances, are also stepping up enforcement patrols near City Hall and Snows Court – the alley between 25th and 26th streets and K and I streets where bottles are landing. Hay said no injuries resulting from the incidents have been reported.

Hay said the local community should not have to deal with such “egregious conduct.”

“If this behavior reoccurs this academic year, we will recommend closing down all of the balconies in the building in order to protect residents in the surrounding neighborhood,” he said.

City Hall resident Leah Lawler, though excited to have a balcony, is surprised by the repeated bottle throwing.

“I think it’s just silly that it happened more than once,” she said.

Vandalism has been a recurring problem at University residence halls. Last December, GW sought to nip chronic cases of “destruction” in Ivory Tower in the bud by installing 36 cameras – at a cost of $60,000 – throughout the hall. Hay wouldn’t say whether UPD actively monitors the security cameras in Ivory or watches the films when crimes are reported.

Ivory, plagued by punched-out ceiling tiles and trashed hallways last fall, saw 25 cases of destruction from Sept. 1 to Dec. 6, 2010. There have been 17 cases of destruction in the building this calendar year, despite the surveillance cameras.