Parachutists on a trip in western Slovakia survived a mid-air collision with another plane by jumping out moments before the crash.
The first images from the crash site, broadcast on Slovak news channel TV Markiza, showed the burnt-out wreckage of one of two L-410 twin-engine planes involved in the accident.
Juraj Denes, an official with the government air accident investigators agency, said some survivors had managed to parachute free before the two planes crashed at an altitude of around 5,000ft.
He said preliminary reports suggested around 40 parachutists were on board the planes at the time.
A part of the wreckage sits amongst the trees as firefighters explore the site of the wreckage
The smoking wreckage is seen on the forest floor, 7 people have died in the accident
Firefighters inspect the crash site of two sport planes near the village of Cerveny Kamen, Slovakia,
A witness told the Dennik newspaper: "I heard the crash and ran [to the site of the accident]. I saw one of the aircraft falling to the ground and people jumping from it."
The TA3 news channel said 15 parachutists were still missing. It added that they were training for this weekend's air show in nearby Slavnica.
Health minister Viliam Cislak and interior minister Robert Kalinak were heading to the crash site.
Seven people have been confirmed dead so far, according to fire service officials, while three search and rescue helicopters have been dispatched to the scene.
The crash occurred in a hilly area near the village of Cerveny Kamen, around 30km from the capital Bratislava and not far from the border with the Czech Republic.
A spokesperson for the Slovakian rescue services confirmed that those on board had been civilian parachutists, and that they were rehearsing for an air show at the time of the crash.
Additional reporting by agencies
