A family member went to check on Angel Santiago Delacruz, 83, at his home at 201 Rose St., and found him dead in his bedroom, said Debbie Tanna of the sheriff's office.
The man, Delacruz's son-in-law, told detectives that his estranged wife, Delacruz's daughter, knocked on his door the night before and got no answer.
Authorities initially thought Delacruz's death was an accident, but a medical examiner said he died of asphyxiation, Tanna said.
Lt. Charlie Disponzio of the Cumberland County Sheriff’s Office said robbery appeared to be the motive – a few hundred dollars in cash was missing from the home.
Family members on Monday remembered Delacruz as a patriot. He spent 21 years in the Army.
Born in Puerto Rico, Delacruz was drafted during the Korean War and served two tours in Vietnam. Three of his children pursued military careers themselves.
Juan Delacruz said his father inspired him to join the military. “He set the standard in my family, in my household,” he said.
When Angel Delacruz found out one of his nine children was in the World Trade Center during the Sept. 11, 2001, terrorist attacks, he was ready to fight.
"When my sister died in 9/11, he wanted to go. He said, 'I'm gonna go,' and that he was gonna talk to somebody," her sister Evelyn Alicea said.
Alicea said her father was a kind man who would lend money to anyone in need.
"I believe what killed him was his kindness," Juan Delacruz said. "My dad was a good man. You know, if you go knocking on his door, you needed something, he'd help you out."
Family members said Angel Delacruz did not drive and walked everywhere.
"My father's a fighter, so if anything was there, he would have fought anybody," Alicea said.