A stampede left at least 15 people dead after mass panic broke out in a tunnel at a Love Parade techno music festival in Germany.

Overcrowding at the entrance tunnel to a former freight rail station, where the event was being held, sparked the stampede and then a crush among the mainly young festival-goers.

The festival, attended by about 1.4 million people, was not immediately cancelled because authorities feared that could spark a second panic and more chaos at the crowded venue.

‘There was no escape,’ one participant called Marius told the Bild.de website. ‘People were pressed into the wall. I was afraid I'd die.’

Rescue work was hampered by the huge crowds attending one of Europe's biggest electronic music events in fine weather, officials said. People had come from around Europe to the Love Parade with most in the 18-25 age bracket.

Police in the industrial Ruhr city of Duisburg in western Germany had earlier tried to close the tunnel entrance.

Ambulances rushed to pick up victims and police set up an emergency first aid station near the entrance, where live images from WDR television showed thousands of revellers streaming out of the festival and towards the city's main train station.

At first the music blared out and people danced on, unaware of the unfolding tragedy nearby.

Police said the death toll was 15, nine women and six men, with at least 15 more injured. There were no further details immediately available about the dead.

Police tried to resuscitate people with the kiss of life. Some media reported at least 100 had been injured in the crush.

Images from the venue showed the music still playing as rescue helicopters buzzed overhead, and WDR reported mobile phone networks had failed because they were overloaded.

‘The emergency workers have problems getting to the area due to the massive crowds,’ a fire department spokesman from Duisburg said.

The annual event, now with a backdrop of electronic dance music such as House, Trance and Techno, flamboyant outfits and energetic dance moves, was first held in Berlin in 1989 as an event to promote peace through music.

It moved from Berlin from 2007 onwards after disagreements with the city authorities over logistics and security and has been held in several other German cities in recent years.

Internationally, similar Love Parades have taken place in Zurich, San Francisco, Mexico City, Acapulco, Vienna, Cape Town, Tel Aviv, Sydney, Santiago, Rio de Janeiro, Oslo and Budapest.