Police on Monday said they have arrested one man who is a suspect in Sunday's mass shooting in Sacramento that killed six people and wounded 12 others.

Dandrae Martin, 26, was identified as a "related suspect" and was booked on assault and illegal firearm possession charges, according to a release from Sacramento police.

CNN is seeking comment from legal representation for Martin. He is scheduled to appear in court Tuesday at 3 p.m. PT (6 p.m. ET).

During the initial investigation, detectives found more than 100 shell casings and discovered at least three buildings and three cars that had been hit by bullets.

"There were a lot of shots fired that night, and hence the complexity of the investigation," police Chief Katherine Lester told CNN affiliate KCRA.

Lester said Sunday there were multiple shooters and a large fight occurred before the gunfire.

District Attorney Anne Marie Schubert said in a statement that Martin has not been arrested for any homicide in the incident.

"The investigation is highly complex involving many witnesses, videos of numerous types and significant physical evidence," Schubert said.

"This is an ongoing investigation and we anticipate more arrests in this case." The prosecutor would not comment on specifics.

Police served search warrants at three homes and at least one handgun was recovered.

Sacramento shooting