East Lansing police Capt. Tom Johnstone said Atherton became aggressive with friends at an apartment on the 200 block of River Street and was restrained. Friends then called 911 at about 12:35 a.m. after discovering Atherton motionless and not breathing.

Police are still investigating the cause of death.

Atherton’s father, Bryan Atherton, said the scuffle was a case of good friends horsing around and was not responsible for his son’s death.

“Somehow, some way, his heart stopped,” Bryan Atherton said. “It wasn’t anything more or anything less.”

Robert Atherton had been drinking at East Lansing bars Friday night, but friends said he stopped before going to the apartment and alcohol was not a factor in his death.

“I think people are getting the idea that it was a wild and crazy party, but it wasn’t,” said Michael Thornton, a friend of Atherton’s since childhood. “I just don’t want people to think that just because it’s on a college campus and it’s (early) in the morning it was an alcohol overdose.”

Others said the festivities were coming to an end.

“The three guys who lived there and him were winding down for the night,” said Mike Anderson, Atherton’s friend and roommate since freshman year. “His blood alcohol content wasn’t high enough to cause his death.”

Anderson said medical officials ran tests to determine his blood alcohol content.

Police responded to the scene within six minutes after the 911 call, Stickel said. Paramedics performed CPR until reaching Sparrow Hospital.

Anderson said Atherton went into cardiac arrest early Saturday and was put into an induced coma before being taken off life support Sunday.

Anderson said he didn’t believe Atherton had prior health concerns.

Ingham County Medical Examiner Dean Sienko said an autopsy was performed Monday but results won’t be available for several weeks. Sienko said his office is still acquiring Atherton’s medical records, which could take a few days.

Atherton was known among friends and family as a sports enthusiast who loved playing games as much as being a spectator.

“We went to different junior highs, but I would play basketball against him a lot, so I always knew who he was because he was the best,” said Ben Stickel, an accounting senior and roommate of Atherton’s.

“I went to high school with him, and he was probably the best basketball player at our high school. That’s what everybody knew him for.”

More than 100 people gathered at the hospital to support Atherton, a fact friends and family said reflects his social nature.

Those close to Atherton said he came from a long line of MSU graduates and bled green and white.

“Probably the three and a half best years of his life were spent in East Lansing,” Bryan Atherton said.

A funeral is planned for Thursday in Shelby Township, but a time has yet to be announced.