FRESNO, Calif. (AP) — Police searched Monday for two assailants who sneaked into a backyard party in Fresno and opened fire on a small crowd that had gathered to watch football on television. Four people were killed and six wounded.

The house where a group of Hmong family and friends got together was deliberately targeted on Sunday evening, but the shooters fired at random once they saw men in the yard, police said.

“They fired randomly into the crowd. It does not appear that they were targeting any individuals, and once they fired, they fled,” Fresno Police Chief Andrew Hall said.

Hall said there was no immediate word on a motive, and so far there was no indication that any of the victims knew their attackers, though most could not see them. They described seeing only flashes when the semiautomatic pistols were fired. Officers went door-to-door looking for surveillance video that might help them track down suspects.

The party “was not described as being out of control in any way. It was just a family event,” Hall said. The chief said the shooting scene was graphic and that officers are making the case a priority.