Police in Sanford said Tuesday they have not closed the case on an alleged mugging that may have claimed the life of a Washington County man.

Exactly what happened the night of Aug. 29 on Henry Avenue in Sanford is still being investigated.

Frederick James Newman Sr., 51, of Princeton died Friday as a result of what family members called “battling the side [effects] of a mugging in Sanford,” according to Newman’s paid obituary in the Bangor Daily News. Newman died of an infection after being treated for injuries suffered in the attack, they later said.

Two people have been summoned in connection with the incident, according to Sanford police.

Gary Lanoie and Shawn A. Freeman, both 19 and of Sanford, have been charged with misdemeanor assault.

Newman’s family members described the August incident this way:

Newman and his sons were on their way to his brother’s wedding in Florida. They had gone to Sanford, a York County city of 20,000, because a family friend had offered to drive them to the Manchester, N.H., airport. “In two hours’ time he would have been on a plane flying down to his brother’s wedding,” Newman’s father, Everett Newman, said Tuesday.

According to police and family accounts, Newman’s son Daniel was walking down a Sanford street when he asked some men for a cigarette. He said there were five men. When they didn’t give him one, he went inside a friend’s house for a cigarette.

“I came back outside to smoke my cigarette. [The men] came across the street and started to give me a hard time,” Daniel Newman said.

Fred Newman heard the commotion and joined his son on the street. The men told the Newmans they were part of the city’s Neighborhood Watch Program.

After the men spoke, Daniel Newman said, his father went to shake one of the men’s hands when he was struck on the head twice from behind. “Dad took a couple of them to the ground after he got hit. He let one of them go. I took one to the ground and put him in the hospital and stuff; it was quite an ordeal,” Daniel Newman said. The son said he also suffered some blows to the head.

Police were called.

Maj. Gordon Littlefield of the Sanford Police Department confirmed Tuesday that there had been an altercation and that after the fight the men ran off. He confirmed that Fred Newman had taken “two of the men to the ground.”

Newman was taken to a nearby hospital suffering from head injuries, including a cut lip.

After Fred Newman returned home, his son Jeremy said, his jaw became infected. The family took him to hospitals in Calais and Bangor.

“The infection spread to his nasal cavities,” Jeremy Newman said. “He was treated for the injuries. I don’t know exactly what happened, but they didn’t seem to catch what the problem was. The infection spread to his brain.”

Newman’s father said that when he and his wife, Virginia, returned from Florida to Maine, they found their son in desperate circumstances. “He got beat up worse than they thought he did,” Everett Newman said.

The official cause of Newman’s death has not been determined, and the results may not be known for months, a spokesman for the state medical examiner’s office said.

Newman worked for Georgia-Pacific Corp. and later Domtar Inc. for 31 years after the Montreal-based company bought G-P’s Baileyville mill.

“He was as strong as a horse,” Jeremy Newman said. “He worked 80 hours a week. He was a strong man and a dedicated father.”

“If the medical examiner’s office makes a medical determination that this is a direct result of injuries sustained during the altercation, then the matter would be reviewed by the Attorney General’s Office, and if they think it’s appropriate they would notify the [Maine] State Police … and have them look into it further,” Littlefield said.

Everett Newman said his son was a good father and was ready to help anyone anytime.