Joe Jaskolka has a simple request for Philadelphians: When the clock strikes midnight Friday, don't shoot off guns.

Jaskolka was struck in the head by a celebratory bullet when he was 11. Now 23, he uses a wheelchair, has lost the use of some limbs, and has undergone dozens of operations.

"It's a senseless act, firing a gun in the air and not thinking where it's going to end up landing," he said at a news conference Thursday, flanked by members of the Police Department and District Attorney Seth Williams. "Please don't end someone else's life. It may not be yours, but it is someone else's."

It might seem like common sense not to fire a gun into the air in a densely populated urban area. But residents of Philadelphia do it every New Year's Eve, officials said.

Police received 177 reports of gunshots fired between 10 p.m. on Dec. 31, 2009, and 2 a.m. Jan. 1. On an average night, the department might receive 10 or fewer such calls, Lt. Raymond Evers said.

Williams warned that harsh penalties await anyone who fires into the air.

Those caught could be charged with reckless endangerment, which could carry several years in prison. If a bullet hits someone, the shooter could be charged with aggravated assault, attempted murder, or worse.

"We don't want Philadelphians to be idiots on New Year's Eve," Williams said. "We want people to have a good time. We want them to be safe."

Jaskolka and his father, Gregory, hold a news conference each year to remind people of the dangers of reckless shooting.

"We went from having an annual New Year's Eve party to having an annual news conference," Gregory Jaskolka said.

Jaskolka was hit on Jan. 1, 1999, while walking with relatives along Fernon Street in South Philadelphia. The bullet that hit him is still lodged in his head, and his assailant has never been caught.

Deputy Police Commissioner Richard Ross warned that patrol officers would be on the lookout Friday night for shots being fired.

"We're looking specifically for people who are going to do irresponsible acts like this," he said. "Please, enjoy yourself responsibly. Ring in the new year in a good way, and don't put somebody else's life in jeopardy."