Epps, who surrendered Tuesday night and was arraigned Wednesday morning, was being held at the Delaware County jail with bail set at $100,000 on misdemeanor charges that included assault, harassment, and the making of terroristic threats.
In the video, the assailant can be seen engaging in conversation the older man, who was sitting in the Aronimink station about 1 p.m. June 11. He then turns and delivers a vicious - and audible - sucker punch to the man's head. The four then ran off.
The victim said he called 911, but "no one answered the phone after a minute and 41 seconds - exactly a minute and 41 seconds. So I hung up. Damn good thing I wasn't bleeding to death. I'd be dead by now."
Chitwood said the county, which is responsible for the 911 system, had been alerted that "something's wrong there."
Chad Brooks, chief of operations for county emergency services, said the 911 call was received but the operator failed to press the victim for details about the incident. When the victim asked to talk to police, the operator provided him with a number for the Upper Darby department.
Right after the video was posted on Facebook, police said, they were inundated with calls from outraged viewers.
Chitwood said Epps' three companions should surrender.
"Come in, because we are going to get you anyway," he said.
Though he said he holds no grudge, the victim, who did not give his name and was not identified by authorities, on Wednesday called the teen a "little punk" who deserves what he gets and who should be prosecuted to the fullest extent of the law.
"You don't hurt people," he said. "My family believes in fighting for peace."