FAIRFIELD, Calif. -- A federal arrest warrant is being sought against Henry Don Williams, who is accused of shooting Fairfield City Councilman Matt Garcia and likely fled the state, Solano County District Attorney David Paulson said Tuesday.

Williams, 32, is believed to have fired shots on Sept. 1 that fatally injured 22-year-old Garcia, an up-and-coming leader who campaigned on a platform of curbing youth violence.

Paulson also said he has decided to rearrest Gene Allen Combs and Nicole Stewart, who are accused of playing a role in the Cordelia shooting.

Combs, 45, and Stewart, 33, were arrested Saturday and booked into Solano County Jail on suspicion of murder and use of a firearm, police said.

Paulson said the charge against Stewart may be downgraded to accessory to murder. Combs will likely still face a murder charge.

Paulson explained that the rearrests are necessary to give police more time to go over evidence in the case. Combs and Stewart are now set to be arraigned on Thursday.

Garcia was in the wrong place at the wrong time and was not the Williams' intended target, Paulson said.

Authorities believe Stewart and Combs were in a car used by Williams at the time of the shooting.

The Fairfield City Council is looking to appoint someone to the vacant seat left by Garcia by Oct. 2.