Organisers of Germany's Love Parade say the dance music festival will never be held again, after 19 people were killed in a stampede over the weekend.

An Australian woman was among those killed in the stampede, while more than 300 party-goers were injured, after crowds panicked in an access tunnel in the town of Duisburg, western Germany.

Questions are being asked as to why a venue with a single entry point was chosen to host an event that attracted more than a million dance music fans.

Police and organisers have begun to investigate how the event, which is supposed to promote peace, ended so disastrously.

Witnesses said panic spread after police tried to turn back fans against the flow of thousands streaming into the festival area through a disused railway tunnel.

People tried to climb walls to get out of harm's way, but many were crushed by surging crowds desperate to get out of the tunnel to safety.

At the tunnel exit, desperate people escaped any way they could. Amongst them was Sahil Bhate.

"I got through and then there was a serious rampage behind me," he said.

"I just had to make a break for it and eventually I found a collapsed bank which people were just running up ... I was getting pushed forward and if I hadn't moved, I would have still been crushed.

"I mean, people next to me, I could see them on the floor lying down and they had trample marks on their face and nobody was helping them because nobody could reach them."

Amy Chapman was also caught up in the chaos. She had been worried even before she got into the long tunnel and had to climb out at the other end.

"They helped us climb up the banks and they tried to get us out of the chaos but the police just seemed to stand there and themselves didn't really know what was going on," she said.

"It's stupid to think that so many millions of people can go in and out of one street and that it would be orderly.

"As we were trying to get in at around two o'clock, everyone was pushing and shoving and you couldn't really breathe and that was outside in the fresh air. I can't imagine how it was in the tunnel."

The festival has been running for more than 20 years, and was first held just before the fall of the Berlin Wall in 1989.

Parade organiser Rainer Schaller expressed his deep sympathy for the victims and their families as he announced that the 21-year-old parade was coming to an end.

"The Love Parade has always been a cheerful and peaceful event but will be overshadowed in the future by the events of yesterday," he said.

Duisburg's mayor has appealed for people to wait for the result of a police inquiry before blaming anyone.