Officers responded to reports of a fight in the 1100 block of Bedford Way at 3:10 a.m., police said.
When police arrived at the scene, several suspects ran away in different directions. A loaded .45-caliber revolver was found in the street, police said.
While officers were on the scene, a 19-year-old man called 911 and told operators he had been stabbed, according to police.
Officers found the victim a few blocks from Bedford Way at the intersection of Nut Tree Road and Northampton Court, police said.
The 19-year-old had been stabbed in the abdomen and the upper back, police said. He was taken to the University of California at Davis Medical Center in Sacramento by ambulance with injuries that were not life threatening.
The victim could not provide details to who stabbed him, police said. Vacaville police also could not determine who owned the revolver left in the street.
The stabbing does not appear to be gang related and there is no suspect information, police said.
Anyone with information about the incident is asked to call Officer Greg Eisert at (707) 449-5200.