Four people were killed and six others wounded in a shooting in Fresno, California on Sunday.

"Everyone was watching football this evening when unknown suspects approached the residence, snuck into the backyard, and opened fire," Fresno Police Lt. Bill Dooley said of the shooting, per the Associated Press's Sunday night report.

The shooting occurred around 6:00 p.m. Sunday night at a backyard party where guests were watching a football game. Once responding authorities arrived to the scene, three people were found dead in the backyard, while a fourth person died later at a nearby hospital.

CNN reports that as many as 40 people, including children, had gathered at the residence. The four who were killed, per comments given to reporters by Fresno Police Deputy Chief Michael Reid, are said to be men whose ages range from 25 to 30. At the time of this writing, no information on the suspect' identity or relationship to those at the party had been released.

"We are going to do everything we can to find out who the perpetrators are and bring them to justice," Reid said Sunday.

Also on Sunday, the Sacramento Bee notes, a man in his 20s was fatally shot in southeast Fresno. Authorities have not said whether there is any connection between the two shootings.