PRAGUE (AP) — Two planes carrying dozens of parachutists collided in midair Thursday over western Slovakia, killing seven people, officials said. Thirty-one others on board survived, some by jumping out with their parachutes, officials said.

The crash took place Thursday morning about 0720 GMT (2:20 a.m. EDT) near the village of Cerveny Kamen, said Zuzana Farkasova, a spokeswoman for the Slovak firefighters. Rescue workers used helicopters to reach the crash site in the White Carpathians mountain range that forms the border with the Czech Republic.

Peter Bubla, spokesman for the Health Ministry said 38 were on board the two planes and 31 survived. Five people needed some medical treatment but nobody was hospitalized, he said.

Juraj Denes, an official with the Slovak Air and Naval Investigations Bureau, a government agency that investigates plane crashes, said the two L-410 transport planes collided at an altitude of 1,500 meters (4,921 feet).

He said the passengers on board were parachutists and some from one plane survived because they managed to jump out before the collision.

Juraj Gyenes of the same aviation agency told TA3 news television that the dead included the two crew members from both planes and three parachutists.

TA3 reported the parachutists were training for this weekend's air show in nearby Slavnica.

"All of a sudden, I heard a big blow," one witness told TASR, the Slovak news agency, in a news video. "Then, it roared. I thought some pieces were falling, but it could be the parachutists."

Slovak Health Minister Viliam Cislak and Interior Minister Robert Kalinak visited the crash site, where wreckage from the planes smoldered among the dense mountain forest.