CHICAGO (CBS) — A multi-state manhunt was underway Monday, after a man shot and killed an elderly man in Cleveland and posted video of the murder on Facebook Live.

The FBI, the U.S. Marshals Service, and police across the Midwest were searching for 37-year-old Steve Stephens, who allegedly claimed to have committed multiple other murders, which have not been verified.

Authorities said Stephens could be on the move in the Midwest. Investigators repeatedly have requested he turn himself in.

steve stephens Police Seek Suspect In Cleveland Murder Posted On Facebook Live

Steve Stephens (Source: Facebook)

Cleveland Mayor Frank Johnson has sought to reassure the public amid the ongoing manhunt.

“I want the public to know that we are on it,” he said.

On Sunday, around 2 p.m. Eastern Time, Stephens allegedly broadcast video of himself pulling up to a 74-year-old man walking down the road, demanding the man say a woman’s name, and then shooting the man in the head. The gunman in the video then walks away and says the elderly man is dead because of the woman, believed to be Stephens’ ex-girlfriend. The video has since been removed from Facebook.

The family of the victim, Robert Godwin Sr., said he was walking home from an Easter celebration at the time.

Stephens also allegedly alluded to being a serial killer in another Facebook post claiming he killed 13 people, and would keep killing.

Investigators don’t believe Stephens has killed anyone besides Godwin, however.

“We’ve searched high and low throughout the city; places that were mentioned in the Facebook post, as well as places that weren’t,” Cleveland Police Chief Calvin Williams said.

Authorities have not found any other victims.

Williams said detectives spoke with Stephens on the phone early in their investigation.

“They tried to, of course, convince him to turn himself in,” he said.

Police have not confirmed or denied reports that Stephens’ cell phone pinged to a location near Erie, Pennsylvania, after the killing. Instead, authorities have urged the public to look for a white Ford Fusion they believe Stephens is driving.

“The goal here is to find Mr. Stephens before any other crimes are committed,” FBI Special Agent Stephen Anthony said.

Stephens is described as a 6-foot-1, 244-pound African American man. He is balding, has a full beard and is believed to be wearing a dark blue and gray or black striped polo shirt.

Williams said he’s confident police will find Stephens, even if he does not turn himself in.

Authorities have warned that several fundraisers for Godwin’s family have been posted online, but none are legitimate.

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