A deputy who happened to be patrolling the area apparently foiled what could have been a massacre as a man authorities described as a jilted lover opened fire in a home of 10, killing two and wounding two others, sheriff's officials said.

The gunman was also wounded when the deputy's bullet grazed him in the 3:40 a.m. violence at 21920 Devlin Ave. in Hawaiian Gardens, sheriff's officials said. The deputy heard automatic gunfire, later determined to be coming from AK-47 assault weapon, and rushed to the home only to find the suspect exiting, authorities told KTLA News.

“As we arrived, we heard the shots on the street, so our deputy did a fantastic job, knew it was an automatic weapon — it was an AK-47 — pulled his AR-15, encountered the suspect on the street, fired two shots, hit him both times, once in the head,'' Undersheriff Larry Waldie told KTLA.

The station identified the suspect as 27-year-old Joseph Mercado. He allegedly shot and killed killed his fiancee and her brother. A can of gasoline he allegedly had might have been intended for use as an incendiary agent, authorities said.

The woman's mother was in critical condition, according to KTLA. The condition of the father was not known. Mercado was booked on suspicion of murder.

-With reporting from Weekly wire services. Got news? Email us.

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