A 35-year-old male wedding guest was shot dead and another was injured after a group of uninvited guests were not allowed into the reception, The San Francisco Chronicle reported.
After the guests were turned away Saturday night, they returned to the Niles, Calif. banquet hall with a handgun and shot the two victims, the newspaper reported.
It was not clear how the two victims knew the married couple.
"It's a terrible tragedy," John Weed, the owner of the hall told the Chronicle. "You're just astounded. How can anything like this happen?"
The Alameda County anti-gang specialists are assisting with the investigation, the newspaper reported.