He said Muhammad, who used the alias "Black Jesus" and was wanted in the killing last week of an unarmed security guard outside a motel in the city, had indicated in postings on his Facebook page that he hated white people and the government.
Authorities say the man fired 16 rounds in one minute.
Police said at the time that Muhammad was homeless and considered armed and risky.
Public records show Kori Ali Muhammad, who is accused of going on a shooting spree in Downtown Fresno, has a criminal record out of Sacramento.
California police have arrested a man they believe shot and killed three people in three different locations Tuesday in Fresno, California.
Dyer said his department had contacted the Federal Bureau of Investigation over the incident. While police were responding to the scene, a PG&E pickup truck pull up to Fresno Police headquarters on Fresno and M Street and notified police that his passenger had been shot near Mildreda and Franklin avenues.
The utility says in a statement it's cooperating with law enforcement as they investigate what led the suspect to open fire Tuesday at four locations within a block. After that, he encountered another man, who he shot and killed, Dyer said. The imam said he is consulting with other faith leaders.
The victims are all white men between the ages of 34 and 58. "We offer condolences for the victims, we pray for the victims and their families". He was already wanted for a separate killing from last week, in which a Motel 6 security guard in Fresno was gunned down.
Fresno is an agricultural hub in California's central valley, about 170 miles southeast of San Francisco. Several more gunshots were detected nearby, Dyer said.
Fresno city spokesman Mark Standriff says county offices are on lockdown, and people have been urged to shelter in place. Hes not known in our community, and we are in touch with other communities to see if he was a member or not.
Ashlee Wolf of Catholic Charities told the Fresno Bee newspaper (http://bit.ly/2oK6Vzc ) the shooting happened at a bus stop near the charity.
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.