The victim was identified as 45-year-old Sean Daniel Winegar of Corona, according to a news release.
Winegar's body was found between F and G streets shortly after 3 a.m., according to the release.
No information is known about the suspect or motive. The investigation is continuing, and police ask anyone with more information to call Detective John Munoz at 909-384-5630 or Sgt. Gary Robertson at 909-841-5361.