Updated

Police are searching for a group of men who investigators say targeted sleeping homeless men in a pre-dawn beating spree. One homeless man died, and one of the attacks was caught on a university surveillance video.

The attackers — described as a group of two to four young white males — will face murder charges, police said.

"It's senseless. If you look at these kids, it was almost like it was fun and games for them," said Fort Lauderdale Police Officer Scott Russell. "It looked like they were laughing and finding great joy in what they were doing, which made it more horrific."

Norris Gaynor, 45, died shortly after 8 a.m. Thursday from his injuries at Broward General Medical Center, police said. The two other homeless men were listed in serious condition at the hospital. They have not been identified.

The video shows two men chasing and beating one homeless man, who had been sleeping on a bench shortly after 1 a.m. Thursday near Florida Atlantic University, with what appear to be baseball bats.

"It looked like they were going for the head," said Fort Lauderdale police detective Katherine Collins.

The homeless man found a security guard who called 911, and the 58-year-old man was taken by paramedics to Broward General Medical Center with head trauma and defensive fractures, authorities said.

The scene was chillingly similar to the two beatings that followed early Thursday near the Broward Center for Performing Arts and a church, investigators said.

Gaynor was sleeping around 2:30 a.m. on a secluded park bench near the performing arts center before he was attacked, police said.

A third homeless man flagged down a fire crew passing a church 3 miles away from the performing arts building just after 4 a.m., authorities said.

"He claims that while sleeping he was attacked," said Assistant Chief Stephen McInerny with Fort Lauderdale Fire-Rescue.

Authorities are urging anyone with information to call Crime Stoppers at 954-493-8477.

Fort Lauderdale police and homeless advocates on Thursday distributed fliers about the beatings and warned people to sleep in well-lit, busy locations if they can't reach a shelter.

"We wanted to make sure that if they knew of people being beaten, or had seen the suspects out on the street, that the detectives on the case had the information," Officer Jamie Costas said.

According to the Washington-based National Coalition for the Homeless, 386 homeless individuals have been attacked nationwide since 1999, resulting in 156 deaths.

Four teenagers pleaded guilty last month to fatally beating a 53-year-old homeless man in Daytona Beach in May. They will be sentenced Feb. 21. A fifth teen still faces still faces an aggravated battery charge and is free on $50,000 bail.