Vacaville residents Richard Marcham Perez, 20, and Cameron Scott Silva, 21, were found dead inside an apartment in the 500 block of William Street around 1:50 a.m., Lt. Randy Weaver said.
Autopsies on the men were completed today, but police have not said how many times they were shot.
Sarah Jane Berkheimer, 21, of Vacaville, was found on the street outside the apartment suffering from gunshot wounds. She was taken to the University of California, Davis Medical Center in Sacramento and is expected to survive, police said.
None of the victims lived at the residence where the shootings took place, but all three knew one another and the suspected shooter, Richard Ruben Calkins, police said.
Soon after the shooting, Calkins, 18, allegedly got inside the lobby of the Police Department at 660 Merchant St. through a door that did not lock properly and smashed several windows with a handgun, Vacaville city spokesman Mark Mazzaferro said.
He was confronted by officers when he left the building and allegedly refused their commands to drop the gun and raise his arms, police said.
Police shot him with a Taser, and he fell on the steps of the Police Department, causing him to suffer a head injury, police said.
He was in guarded custody at a hospital today, Weaver said.