Report:

A melee outside a Temecula Mexican restaurant that left one man dead and another recovering in the hospital started when a group of men attacked an off-duty Costa Mesa police officer from behind, Riverside County sheriff’s investigators said Tuesday.

The officer, whom authorities decline to identify, was sitting down outside the Bank of Mexican Food restaurant Saturday night because he “didn’t feel well,” according to investigators. Some time after, Shaun Vilan, 30, Taylor Willis, 22, and two or three other men attacked the officer from behind, witnesses not associated with either party told authorities, sheriff’s investigator Jerry Franchville said. One of the attackers smashed a chair or other hard object into the officer’s head, sending him to the ground as blood poured from his head down his face, Franchville said.

The officer showed his ID and said loud enough for witnesses to hear that he was an off-duty cop, Franchville said. When the men continued to attack, the officer pulled out his gun and shot five times at his two nearest assailants, hitting Vilan and Willis twice each, investigators said. Vilan, Willis and the officer were all taken to Inland Valley Medical Center, where Vilan was later pronounced dead.

Saturday night’s brawl happened during a busy time of year for Temecula, when tens of thousands descend on the city for the annual Temecula Rod Run, a classic hot rod car show. Vilan’s friends and family, including his 7-year-old son, Dillan, were there to support Vilan’s brother, who had a car in the show, according to Vilan’s family. The officer was in town visiting friends, according to investigators.

Vilan was previously convicted of two counts of assault with a deadly weapon and sentenced to seven years in prison, according to court records. He was out on parole, authorities said.

While Vilan’s family agrees that some kind of confrontation with the officer spilled out onto the streets, from there the accounts differ. Lewis and Michael Brooks were with their brother, Vilan, through the whole confrontation, family members said. They claim the officer and his friends waited outside for them.

He was drunk and out of control, and shot at them as they fled, they said. The officer’s friends tackled him after he started shooting and that might be how he got his head injury, they said.

The officer is recovering at home and is on paid administrative leave, Costa Mesa police officials said.

Franchville said he doesn’t know when the investigation will be completed.

JOSEPH SERNA may be reached at (714) 966-4619 or at joseph.serna@latimes.com.