More than 30 youth group members and volunteers have been injured after their bus crashed in a motorway in the US state of Pennsylvania. 

The passengers were coming back from a church student retreat organised by Lives Changed By Christ church. 

The crash happened shortly after 2.30pm on Sunday in Schuylkill County, about 100 miles northwest of Philadelphia. 
 
All passengers, but one, were transported to local hospitals with different levels of injuries with at least five of them in critical condition. Four had to be airlifted out by helicopters. 

The bus was one of three buses returning from Lake Champion in New York, the other two made it back safely. 

In a statement, the church's senior pastor, David Ashcraft, said that two-thirds of those hospitalised have already been discharged while the other third remains under observation. 

He urged people to continue to pray for those in hospital and their families. 

"We ask that you would continue to pray for each student and their families during this very difficult time. Specifically, we are asking God for the comfort and healing of each student along with wisdom and skill for the medical teams that care for them. Additionally, we ask for peace and comfort for the families of each of the girls involved.

"I love our LCBC family, and families pull together in times of need. And now is the time for our entire LCBC family to come together in prayer to support these girls and leaders and their families," the statement concluded. 

The cause of the accident is still unknown.