A Utah man is looking for answers after his son, a 20-year-old Marine, was found dead Saturday at a friend’s residence in Kalihi.

Lance Cpl. Samuel Johnson of North Logan, Utah, was discovered unresponsive and pronounced dead by first responders, Marine Corps officials said.

“All we know is he went to a friend’s house and the friends went to the beach and they came back and he was dead,” said the Marine’s father, Rex Johnson.

Honolulu police said Johnson’s death at a house in Kalihi did not appear suspicious. Autopsy results were pending.

Samuel Johnson was a field artilleryman with the 1st Battalion, 12th Marine Regiment. He deployed to Japan, came back in March and got married, but the relationship didn’t work out, his father said.

“I know he’s been down a little bit, but he seemed to be recovering,” Rex Johnson said. The Naval Criminal Investigative Service is investigating the death.