ANTIOCH -- Police are investigating a drive-by shooting in which two men were shot by an unknown suspect Monday morning outside a house.

Officers were called about 10:15 a.m. to a residence at 2318 Mandarin Way for a report of a double shooting, Sgt. Santiago Castillo said.

A preliminary investigation revealed the victims, a 26-year-old from Richmond and a 27-year-old man from Antioch, were standing outside the home when someone drove by them and began shooting from a car, police said.

Their conditions were not released, but both are expected to live, Castillo said.

Police are investigating the motive for the shooting and no arrests have been made.

Contact Natalie Neysa Alund at 510-293-2469. Follow her at Twitter.com/nataliealund.