Arrests were made Sunday at the Red Rock Job Corps Center center in Sullivan County.
It prompted dozens of state troopers to respond to the place on Red Rock Mountain.
The Red Rock Job Corps Center trains 16- to 24-year-old students for jobs.
For some reason, a dance planned for Saturday night was canceled, prompting what police called a "disturbance."
State troopers blocked off Route 487 in Luzerne County which leads to the Job Corps Center about five miles up the mountain.
State police cruisers kept on coming to help get Sunday's situation at the center under control.
A day later, folks at the Red Rock Corner Store said what they saw on Sunday, at first, made them wonder if their safety was at risk.
"It blew our minds. At first we didn't know what was going on. All the state cars going up the road with their sirens on, thinking wow something major happened," said Madelyn Bonham.
The Red Rock Job Corps Center is at a former Air Force station near Lopez in Sullivan County. Federal officials said the job training program has about 300 residents from low-income backgrounds.
By late Sunday, three of those residents wound up arrested and charged with aggravated assault. State police said it all started when a dance event was canceled and someone pulled the fire alarms in protest.
State police were called in Sunday when the young women, two from Philadelphia and another from Reading began assaulting staff members, said troopers. Then investigators said the three assaulted state troopers once they arrived.
It was enough to take people around the area by surprise, but not enough to make the owner of nearby Red Rock Mountain Campground concerned for his safety.
"There were a lot of ambulances, police, rescue vehicles, a lot of that type of traffic that is unusual," said Guy Bachman.
There is an investigation underway into what happened at the center in Sullivan County, according to a spokesperson for the U.S. Department of Labor which oversees the Job Corps program.
Job Corps has a zero tolerance policy.
State police said no one was seriously hurt in the violence at the Red Rock Job Corps Center Sunday.