While fireworks are illegal to sell, buy and ignite in Covington, police are more concerned with a harsher threat this New Year’s Eve: gun blasts into the air.

For years, area residents have randomly discharged their weapons — rifles, pistols and even shotguns — skyward as streaming rockets light up the sky.

With the boom and crackle of celebratory rockets, sometimes it’s hard to distinguish gunshots from fireworks. But Covington police will beef up patrols to harness what could be a deadly evening if the gun blasts continue tonight, Capt. Jack West said. “We’ve been lucky so far,” he said. “It’s not like New Orleans where there are always reports of stray bullets hurting somebody, but we do have a lot of roof leaks.”

The bullets, he said, often reach the same velocity coming back down to earth as they had when discharged, he said.

“This could kill,” he said.

A prime example occurred in 1996 in New Orleans when a falling bullet fired on New Year’s Eve killed a Boston tourist.

But how much damage a bullet can inflict depends on the angle of the shot, the wind, the make of the gun and the strength of the gunpowder, among other variables. A bullet fired at sea level from a .22-caliber rifle and not aided by wind, for instance, can travel 4,870 feet, or about nine-tenths of a mile, according to a handbook from the National Rife Association. The bullet’s initial speed leaving the barrel is 1,255 feet per second, according to the N.R.A., or 856 miles per hour.

While it was unclear how many reports of such shootings have occurred in Covington, Councilman Matt Faust has heard of scattered incidents, especially “over the last few years.”

“I don’t think it’s a widespread thing,” Faust said. “But it’s a deadly way to celebrate, and if you do it, you’re going to jail.”