All of the victims were aged from 14 to 18 years old, and they were from a summer camp at Stahlman Park in Surfside Beach, a small city about 60 miles (about 96 km) away from downtown Houston, said Sharon Trower, public information officer for Brazoria County.

Five of them were flown to hospitals in Houston by helicopter after the incident, said Trower, adding that other teens were taken to hospitals by ambulance and private vehicles.

None of the injuries were expected to be life-threatening, according to local media reports.

The cause of the ramp collapse is under investigation.

(With UNI inputs)