Sylvester Stallone's 36-year-old son Sage Moonblood Stallone, who appeared with his father in Rocky V, was found dead in his Los Angeles home Friday. 

Police officers were called to the house at 2:17 p.m. and discovered the body. There were no signs of foul play or forced entry. 

"It sounds like a terrible tragedy. He was way too young to die," LAPD Commander Andrew Smith tells PEOPLE.

He adds that reports that Sage died from a prescription overdose are premature. 

"It could have been a heart attack or a stroke," he says, adding the coroner's office will likely spend several weeks on a toxicology report before it can reach any such conclusion. 

Sage's attorney George Braunstein said: "(Sage) was full of life, a wonderful, loving person," says Braunstein. "The last time I talked to him a few days ago he was saying he was getting married, he had a lot of things he was working on and seemed very enthusiastic. There was no indication there was any problem."