Patrick Heard
Stabbing victim Patrick Heard. Courtesy San Diego County Crime Stoppers

A man already in custody in an unrelated criminal case has been re-arrested on suspicion of killing a stranger last month during an apparently random confrontation in El Cajon, authorities said Tuesday.

Daniel Emmanuel Perez, 30, allegedly stabbed 54-year-old Patrick Heard of Oceanside in the throat as the victim was sitting in his car in the 400 block of Graves Avenue shortly before 11:30 p.m. on Aug. 22, according to El Cajon police.

Following the attack, the mortally wounded victim got out of his vehicle, staggered toward a nearby apartment complex and collapsed, Lt. Keith MacArthur said. Paramedics took him to a hospital, where he was pronounced dead.

Detectives determined the slaying followed a “brief altercation” between Heard and the assailant, and that he and Perez did not know each other, the lieutenant said. What prompted the deadly confrontation remained unclear.

Tips from the public to San Diego County Crime Stoppers helped investigators identify Perez, an El Cajon resident, as the suspected killer, according to MacArthur.

Perez, who was behind bars on charges of assault and burglary when he was booked on suspicion of murdering Heard, was being held in San Diego Central Jail without bail pending arraignment in the latter case, scheduled for Wednesday afternoon.

City News Service contributed to this article.