A day to remember - for all the wrong reasons.

A jet aircraft ploughed into several cars on a busy road near an airshow, killing at least seven people.REUTERS

"This has been a day to remember for all the wrong reasons." That was how Rick Easter, a presenter with Premier Christian Radio described the devastating scene he saw on Saturday. "I witnessed the events from the flight line and have been left completely stunned and shocked. I have never seen anything like this before in all my years as an aviation enthusiast."

A jet aircraft ploughed into several cars on a busy road near an airshow, killing at least seven people, police said.

The vintage Hawker Hunter fighter jet crashed onto the A27 road, close to an airport in Shoreham where the airshow was taking place, near Brighton.

All those who died were on the road at the time of the crash, police said, adding that it was possible more bodies might be found overnight and on Sunday. The pilot is in a serious condition in hospital.

The ambulance service said 14 people were treated at the scene, with four taken to hospital.

Video footage posted online showed the plane in the process of executing an acrobatic loop before it hit the ground, causing an explosion which appeared to engulf some cars.

"He'd gone up into a loop and as he was coming out of the loop I just thought, you're too low, you're too low, pull up," the BBC quoted an eyewitness, Stephen Jones, as saying.

"And he flew straight into the ground either on or very close to the A27, which runs past the airport."

Easter, who encouraged prayers for the victims' families, said he and fellow witnesses were stunned, "There was this sound of several thousand spectators gasping, followed by an almighty impact and then the large plume of fire and smoke across the airfield... this was followed by complete silence as the shock of what had been seen, sank in."

Media reports said the pilot of the plane was pulled from burning wreckage.

The crash happened at around 1:20 pm (1220 GMT). Shoreham Airshow cancelled its event, which was due to run into Sunday.

The Hawker Hunter is a single-seater jet which was developed by Britain in the 1950s.

Elswhere in the world, seven people were killed when two planes practising for an airshow collided in Slovakia on Thursday. A U.S. Army parachutist died after he was involved in a mid-air collision with another parachutist at a Chicagoairshow last Saturday.