"These individuals who were chosen today did not do anything to deserve what they got," Fresno Police Chief Jerry Dyer said. "These were unprovoked attacks by an individual that was intent on carrying out homicides today. He did that."
It's too soon to say whether Muhammad, who was homeless and filled his social media feeds with racially charged posts, had ties to any militant groups or causes, Dyer said.
Stephen Hughes, 66, said he and his wife rushed home Tuesday after receiving a frantic call from a neighbor. Hughes came home to see a body draped in a blanket on the sidewalk leading to his front door.
He first thought the shooting was gang-related, but then he noticed the bag of groceries near the body.
"This guy doesn't look like a drug guy. It looks like a guy carrying his groceries home from the store," Hughes said.
Muhammad had a criminal past and was wanted in connection with a shooting last week that killed a security guard at a Fresno motel who had responded to a disturbance. The security guard also was a white man.
On what appeared to be Muhammad's Facebook page, he repeatedly posted "#LetBlackPeopleGo" and encouraged "black warriors" to "mount up." A flurry of posts emerged in the past day.
He wrote that his "kill rate increases tremendously on the other side" and also posted about "white devils." On several occasions, he wrote updates that included the phrase "Allahu Akbar," meaning "God is great" in Arabic.
Muhammad has a criminal history that includes arrests on weapons, drugs and false imprisonment charges and making terrorist threats. He had been associated with gangs but was not a confirmed member, police say.
Muhammad was charged in 2005 with possessing cocaine with intent to distribute, court records show. Federal prosecutors said at the time that he was also in possession of a 9mm semi-automatic handgun and two rifles after being convicted of a felony.
He claimed insanity, and his attorney requested a psychiatric examination for his client, saying Muhammad "appeared eccentric with some bizarre beliefs." A psychiatrist who examined Muhammad believed he had psychosis, Muhammad's attorney said in the court filing.
He also "suffered auditory hallucinations and had at least two prior mental health hospitalizations," according to court documents. His attorney said that Muhammad had "paranoia" and thought the justice system and his defense attorney were conspiring against him, court papers said.
The attorney who represented Muhammad in that case did not return a call for comment Tuesday.
Public records list Muhammad as Cory Taylor and other aliases with addresses in Fresno and Sacramento. A woman who identified herself as Taylor's grandmother said Tuesday that the family last saw him on Easter Sunday. She hung up the phone before giving her name.
Authorities spotted Muhammad running and took him into custody. Police are looking for the revolver.
Police say two of the victims may have been clients of Catholic Charities, which provides a variety of services for refugees, the homeless and those for disabilities.
Catholic Charities doesn't believe Muhammad has ties to the nonprofit, spokeswoman Teresa Dominguez said.
Seyed Ali Ghazvini, imam of the Islamic Cultural Center of Fresno, said Muhammad was not a member of his congregation and he did not recognize him. The imam said he is consulting with other faith leaders.
"We are very sorry for this to happen," Ghazvini said. "We offer condolences for the victims, we pray for the victims and their families."