LOS ANGELES (Reuters) - The gunman who shot seven people around a swimming pool at a San Diego apartment complex, killing one victim before he was slain by police, was distraught over a breakup with a girlfriend, whom he called on his cell phone during the rampage, police said on Monday.

San Diego Police Chief Shelley Zimmerman described Sunday evening’s mass shooting as an act of random violence, transforming what began as a birthday celebration among friends “into a tragedy of epic proportions.”

The gunman was identified as Peter Raymond Selis, 49, who according to court records had worked as an automobile mechanic and filed for bankruptcy twice during the past decade. Those documents showed he was married at least twice with three children.

He was a resident of the La Jolla Crossroads Apartments where Sunday’s violence unfolded, as Selis sat in a lounge chair by the pool and opened fire with a handgun, authorities said.

At least one witness told local media Selis was drinking a beer during the shooting. And at one point, he called his former girlfriend on his cell phone, according to police.

“It is apparent that Selis wanted his ex-girlfriend to listen in as he carried out his rampage,” Zimmerman told a news conference.

She said the gunman also shot at police arriving on the scene minutes after the carnage began, and they returned fire, killing the suspect.

A total of seven victims were struck by gunfire, one of whom died of her wounds, while the other six including two who were listed in critical condition were expected to survive, police said. According to Zimmerman, an eighth person suffered a broken bone while trying to flee.

Local news media reported all of those shot by Selis, four women and three men, were either black or Hispanic, prompting some on social media to suggest the shooting was a hate crime.

But Zimmerman said investigators found “zero evidence to indicate that race played a factor in this terrible and horrific crime.”