Four people have died in a two-vehicle crash on the A3 motorway near Emmerich, North Rhine-Westphalia, Germany.

According to information from the German television station N-TV, it is believed that it was a group of Dutch excursionists traveling in three Porsches.

"There was initially an isolated accident that probably happened due to heavy rain and excessive speed," a police spokesman told the Bild newspaper.

The first Porsche, with two passengers, skidded on the rain-slick road, left the tarmac and ended up in a roadside ditch.

The passengers, however, a 42-year-old man and a 37-year-old woman, escaped unharmed from the impact, as they even extricated themselves from the damaged car.

The 39-year-old driver of a second Porsche following, stopped to help them.

However, while the three people were standing on the side of the road, they were swept away by a third Porsche whose 56-year-old driver lost control, crashing into them and then crashing into the road's guardrail.

All four people were fatally injured.

The only one who managed to survive with minor injuries was the passenger of the third Porsche.

All three vehicles had Dutch license plates for this and at this stage of the investigation authorities believe they were Dutch nationals.