CHICAGO (CBS)– At least four people were killed at a Bears, Rams game watch party in a backyard in California Sunday night.

The incident took place at a party in Fresno, California just before 8 p.m. and police said at least 10 people were shot.

The event was a family gathering with dozens of people in attendance, including several children.

Police said all 10 of the victims are men between the ages of 25 and 35.

Three of them were pronounced dead shortly after the shooting happened. The fourth victim died in the hospital.

The rest are still being treated.

So far, no arrests have been made.

Investigators are still working to determine if there was one or multiple shooters involved in this mass casualty.

Police did say they believe this was a targeted attack, but did not share any early information on a possible motive.