Authorities in the US state of Pennsylvania are searching for nine minors who fled from a juvenile detention center Sunday night after a riot, police said.

Pennsylvania State Police and other law enforcement officers "are looking for 9 juveniles who escaped from Abraxas Academy tonight around 8:00 PM," Trooper David Beohm of the state police wrote on social media platform X.

"The escaped juveniles should be wearing gray pants or shorts and a gray shirt. Call 911 if you spot someone matching that description," he said.

Beohm said a perimeter was established around the youth detention facility in southern Pennsylvania's Morgantown.

"This evening there was a riot at Abraxas Academy," Caernarvon Township Police Department said in a separate statement on Sunday.

Authorities on the scene "have taken back control of the juvenile detention center," it added.

The Abraxas facility offers "detention services" and a "residential treatment program (that) provides specialized care for delinquent male youth between the ages of 14 to 18," according to its website.

It is located about 15 miles (24 kilometers) west of the rural Pennsylvania town where escaped murderer Danilo Cavalcante was captured on Wednesday after two weeks on the run.

The massive manhunt for Cavalcante, a 34-year-old Brazilian national sentenced to life in prison for murdering his girlfriend, ended when he was subdued by a police dog after having avoided drones, helicopters and law enforcement from the FBI to Border Patrol.