Duarte shootings

Cristopher Rossi, 16, was shot to death outside his home on Huntington Drive in Duarte late Monday. Authorities in nearby Monrovia are stepping up patrols in response to the shootings. (Irfan Khan / Los Angeles Times)

The Los Angeles County Sheriff's Department is beefing up patrols in Duarte after three shootings in two days left two teens dead and another man wounded, authorities said Tuesday.

The latest shooting occurred about 11:30 p.m. Monday, when a 16-year-old was gunned down outside his home in the 2500 block of Huntington Drive.

The victim's parents identified him as Cristopher Rossi. He was outside with friends when he was killed, his father, Daniel Rossi, said.

HOMICIDE REPORT: Track killings in L.A. County

"I don't really know what happened," Daniel Rossi said. "I was watching TV. He's in and out all night. He meets his friends there. Then I heard five very loud, what I thought were M-80s. I thought someone set off firecrackers or something."

Daniel Rossi said he peered outside to see if the fireworks were from his son, but didn't see anything. He looked in Cristopher's bedroom to see if he was there. Then he heard a woman scream.

When he went outside, he saw his son lying on the ground.

"I felt for a pulse and everything and couldn't find one," he said.

Paramedics pronounced Cristopher dead at the scene. Authorities said they were investigating whether the shooting was gang-related, but as of Tuesday morning, they had no indication that the 16-year-old had any gang ties.

Police in neighboring Monrovia have also stepped up patrols, authorities said. A conflict between rival gangs may be behind some of the shootings, said sheriff's Lt. Randy Hasnas.

"We're still trying to corroborate things to see if there's a connection," he said. "The investigation is still in its infancy."

Two people were shot Sunday, not far from the scene of Monday's slaying. Just after midnight, 18-year-old Malcolm Mency was gunned down around the corner from his house in the 2000 block of South Broderick Avenue as he walked home from work. Hours later and about a mile away, another man was shot by suspected gang members and survived.

Mency — an 18-year-old black man — was probably shot by a Latino gang member who assumed he was a rival, authorities said. Mency did not appear to be a gang member, officials said.

joseph.serna@latimes.com