Michael Toler, 19, died about noon Sunday, said Capt. Marissa Tindale, head of the detectives division with the Glynn County Police Department.
Shortly after his death was made public Sunday, Police Chief Matt Doering announced a $25,000 reward "for the arrest of the person or persons responsible for one or more of these deaths."
Asked what the reward means in terms of the investigation, he said, "What does the $25,000 mean? It means we need help.''
Doering again said that police have no specific suspect and that officers would resume searching for evidence Monday.
"We are not confining our search to Glynn County. We'll go where we need to go and do what we need to do,'' he said.
"Someone without a doubt walked into that house and killed them. Yes, it could be more than one suspect,'' Doering said.
The Georgia Bureau of Investigation's Savannah crime lab has completed autopsies on four of the bodies, and Doering said he was unsure when all will be completed.
Earlier today Doering wouldn't say whether Guy Heinze Jr., a son of one of the victims, is tied to the deaths. Mr. Heinze was charged earlier today with tampering with evidence and obstructing police in their probe.
"I would not call Mr. Heinze a suspect, but I won't rule him out either," Doering said.
Later he said: "I'm 100 percent certain what happened, and I'm 100 percent certain I know how it happened. What remains is who and the motive."
District Attorney Stephen Kelley went to the crime scene in the single-wide mobile home today. Kelley said law enforcement faces numerous hurdles in solving the case.
"I've seen a lot of crime scenes in my 24 years, and this is the most puzzling," Kelley said. "What makes it so difficult is the fact of the sheer number of victims in one location."
Heinze, 22, is the son of slaying victim Guy Heinze Sr., said the elder Heinze's brother-in-law.
Guy Heinze Jr. is also charged with possession of a controlled substance (Darvacet) and possession of marijuana. He called 911 about 8 a.m. Saturday to report that someone had killed his family at the rural mobile home park 10 miles north of Brunswick.
McIntosh County Chief Deputy William Jennings said the sheriff's office had an open file on a complaint Heinze made against the owner of the park.
Because Heinze was behind on his rent payments for his lot, the owner apparently took possession of the mobile home and sold it to someone else, Jennings said.
Heinze found himself locked out of his own property and called the sheriff's office, which investigated, Jennings said.
Doering said earlier that investigators believe that none of those found inside the trailer were involved in the attack, but they all lived there.
On Saturday, Doering described the crime scene as "horrific" and labeled the deaths the area's worst carnage ever.
Heinze reported finding the victims about 8 a.m. in the mobile home park 10 miles north of Brunswick. County Coroner Jimmy Durden said the victims appeared to have been killed overnight. Their bodies were discovered on the floor and beds inside the mobile home.
Because of the severity of the injuries, their identities and manner in which they were slain could not be readily determined.
Doering said about one-third of his staff of 114, including 20 detectives, are working the case. Federal agencies have offered help.
"There has not been such a number of victims, that I know of, in the history of this county,'' he said.
Hours later, he added: "It's sad anytime this happens in any community. I want our local folks to know that we're taking it as serious as we can take it."