Officers responded to a report of a fight in a parking lot behind 1082 B. St. at about 12:20 a.m., police said.
Buffalo Bill's Brewery is located at that address.
When officers arrived, they found a male in the parking lot suffering from at least one stab wound. Crews attempted to give the male aid but he was pronounced dead at the scene, according to police.
About five minutes later, police responded to a report of a solo car crash in the area of A Street and South Garden Avenue.
When officers arrived at that scene, they found an unoccupied car, police said.
The officers were then notified of two patients that arrived at a hospital suffering from stab wounds. The conditions of the two victims were not immediately available.
The three stabbings are believed to be related but are all under investigation, police said.
Anyone with information about the incidents is asked to call Hayward police at (510) 293-7034.