A sign at the Century Sheriff’s Station in Lynwood warns against illegal gunfire. | Daina Beth Solomon

Every New Year’s Eve, “pops” and “bangs” resonate throughout the Los Angeles area — some from fireworks, and others from bullets blasting into the air.

But the celebratory gunfire has caused serious and sometimes fatal injuries to innocent bystanders, and L.A. County Sheriff’s deputies are planning to step up patrols this year to try to stop the practice and catch offenders.

“Shooting guns to celebrate the New Year is reckless, dangerous, and can be deadly,” Sheriff Lee Baca said Tuesday at a press conference in Lynwood.

Shooting into the air can be prosecuted as either a misdemeanor or a felony, with punishment ranging from one year in jail with a $1,000 fine to three years in prison with a $10,000 fine. When shots result in death, the shooter can be prosecuted for murder.

On New Year’s Eve 2012, the Sheriff’s Department received 93 reports of gunfire. Two people were wounded, and two properties damaged. Baca said he estimated that 400 other incidents went unreported.

The Sheriff’s Department and the L.A. Police Department are urging residents to call 911 at the sound of gunfire – even if it could just be fireworks.

“Certain people don’t call, and if they don’t, we have no way of knowing,” said Baca.

Police say bullets can plummet to earth at 300 to 700 feet per second from a height of up to two miles – collecting enough force to penetrate the skull. Eighty percent of injuries from such gunfire wound the head, shoulders or feet, according to the Centers for Disease Control and Prevention.

Shooting on holidays may appeal to revelers because guns are readily available while fireworks are not, said gunshot wound expert Marie Russell, an assistant professor of emergency medicine at USC’s Keck School of Medicine. (Fireworks that explode in the air are illegal in L.A. County without a permit.)

Arresting offenders is tricky because many shooters dash inside their homes after pulling the trigger, said Baca.

Since 2001, the department has used a ShotSpotter Gunshot Location System at the Century Sheriff’s Station in Lynwood to help law enforcement officers pinpoint the location of gunfire. Its acoustic technology can detect and locate shots within a zone of two square miles — like an “automatic 911,” said sheriff’s Capt. Ernest Chavez.

But even with technology’s help, Baca said, “We’re not catching it all.”

South Los Angeles typically has the heaviest concentration of celebratory gunfire in the county, he said, followed by parts of the Eastside.

Cities across the nation contend with fatal celebratory gunfire on major holidays, with children and women as frequent victims.

The last death by celebratory gunfire in L.A. happened on the Fourth of the July in 1999. Brian Perez, age 9, was playing in the yard at a family barbecue when he was struck by an errant bullet.

In Orange County, 9-year-old Xavier Morales died from a gunshot wound in 2002. A bullet that had been fired into the air on July Fourth in Buena Park tore through his lungs and severed the aorta.

In Maryland on New Year’s Eve in 2012, a 10-year-old was hit by a bullet while watching midnight fireworks. She died the next day. Last summer in Virginia, a 7-year-old boy died when a handgun was fired in the air at an Independence Day celebration.

Bullets can also find their way inside homes. In Detroit on New Year’s Eve 1997, a slug killed a woman who was sitting in her dining room. This year, a Detroit shooting range will offer free entry from morning until 1 a.m. to try to keep gunfire off the streets.