Authorities say that Jordan Vigil, 29, of Hayward was the man whose body was discovered in a home on Omega Avenue, according to a report in the Hayward Daily Review.
No cause of death was released but authorities said Vigil had a criminal history.
Earlier, police had said there are about a dozen persons of interest relating to Monday evening.
Sgt. J.D. Nelson of the Alameda County Sheriff's Office said that as deputies arrived at the 4300 block of Omega Avenue between 6 and 7 p.m. on Monday, about a dozen people who were hanging outside the house quickly ran off.
Deputies found the house to be disheveled with blood everywhere, an obvious sign that a "violent crime occurred there," according to Nelson. They then discovered the body of a man in his 20s lying in the garage.
Police then cordoned off the house and got a search warrant.
"This just goes to show, you never know what's going on at any given time," Nelson said.
The case remains under investigation.
Anyone with information is asked to call Alameda County Sheriff's Office investigators at 510-667-7721.
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