The raid of Your Black Muslim Bakery, which is affiliated with a black Muslim splinter group, was connected to an investigation of three murders in the last six weeks, KTVU, San Francisco reported.
One of the murder victims was Oakland journalist Chauncey Bailey, who was reportedly doing an investigative piece on the group.
Police also raided three Oakland homes, including that of the organization's leader, Yusef Bey IV.
Witnesses of the 4:50 a.m. bakery raid said about 20 police officers assaulted it with rifles and flash grenades, the station said.
Bey's group has been under investigation for more than a year in connection with murders, robberies and kidnappings, Oakland Deputy Police Chief Howard Jordan said.
The group has frequently been connected with violence over the last 30 years, according to KTVU.