A shooter driven by jealousy opened fire and killed four people at a car wash early Sunday morning in Pennsylvania, while a woman hiding in the back of a pickup truck suffered only minor injuries, according to state police and family of the victims.

Police said Timothy Smith, 28, was on life support and not expected to survive after suffering a gunshot wound to his head during the attack at Ed's Car Wash around 3 am in Saltlick Township, a rural town about 55 miles (89 kilometers) southeast of Pittsburgh. Police said it was possible that the gunshot wound was self-inflicted.

Armed with a semi-automatic rifle, a .308-caliber rifle and a handgun and wearing a body armor carrier without the ballistic panels inserted, police said Smith killed 27-year-old William Porterfield, 25-year-old Chelsie Cline, 23-year-old Courtney Snyder and 21-year-old Seth Cline.

Police would not go into details about how Smith knew the victims, but Chelsie Cline's half-sister, Sierra Kolarik, told the Pittsburgh Tribune-Review that Smith had developed an obsession with Cline.

Cline shared a meme on her Facebook page last week that read, "After this week, I rlly (sic) need to get taken out ... on a date or by a sniper either one is fine w me at this point." A Facebook friend of hers named Tim Smith replied, "I could do both."Porterfield's pregnant wife, Jenna Porterfield, 24, told the Pittsburgh Post-Gazette that a state police investigator told her that Smith was a jealous former boyfriend of Cline.

Porterfield said that she was told by family members of other victims that her husband and Cline had spent the past two days together after Cline ended a relationship with Smith. Porterfield said that she and her husband — who were married in November — had been "having some troubles" this month.

"I'm not holding that against Will. We weren't fighting. We were fixing. And if he was with someone else while we were having problems, honestly, I don't care what he did. I'm not going to hold that against him," Porterfield told the newspaper.

"I'd give anything to have him back."Smith was first to arrive at the scene and was parked on the side of the two-bay car wash when Porterfield and Cline arrived, police said. Smith shot them when they got out and walked to the side of the car wash, they said.

Snyder and Seth Cline arrived at the same time and police said Smith opened fire on them. Another woman in the rear seat of the extended cab pickup truck only suffered injuries from broken glass.

Police said Smith had several magazines for the semi-automatic rifle and the handgun.

Cayleigh Myers said she was friends with Seth Cline, Chelsie Cline's half-sibling, and described the construction worker as "very outgoing, very funny and very smart.""You always had fun when you were around him," Myers said. "He would give his shirt off his back for you, anything, it didn't matter what it was, what time it was, if you need him, you could call him.

He was everything."Ed Bukovac, who owns the car wash, told the Pittsburgh Tribune-Review that a neighbor called him around 4 am Sunday and said something was wrong at his business. Bukovac said police were on the scene by the time he arrived and that he had few other details about what happened.

A man who lives nearby told the newspaper that he heard about 30 gunshots over a span of several minutes.

This story has been corrected to change the number of fatalities to four, based on updated information from state police.

AP