Following the Love Parade disaster on July 24 in Duisburg, mayor Adolf Sauerland said that he has received multiple death threats.

The crowd stampede at the free dance event in Duisburg caused the death of 21 people and left 500 injured. A memorial service was held on July 31.

Last month more than 250 people protested in Duisburg and demanded the resignation of Sauerland, the city's mayor.

There has been criticism of Sauerland and the city's authorities for failing to adequately plan for the event. The organizers also have come under fire for allegedly trying to squeeze hundreds of thousands of revelers into too small a space and for allowing only one access point onto the festival grounds.

Now Sauerland has revealed that he has received death threats. "One person wrote to say that someone else had paid him €5,000 [$6,400] to kill me," he told Spiegel Online. "Another wrote saying I should resign immediately or they would blow up a preschool."

The mayor said that he had filed complaints against persons unknown for each threat, that he has been provided personal security guards and that he removed his family from the city as a precaution.

The mayor did not attend the memorial service on July 31, in an effort to avoid causing offense and he reported in the interview that he was not able to watch the memorial service on television. "I don't last all the way through the images posted on YouTube either," he said. "They break you down."

He has since met a mother whose daughter died in Duisburg. "It was very important for me," he said. "We talked through what the mother was feeling, and I too wanted to express my feelings to her and offer her my help. The meeting also gave me a certain measure of hope. I told her that none of us ever wanted something like this to happen. And she accepted that."

Confronted by Spiegel Online that a mother of a victim reported that the only letter she has received so far from Duisburg was a request for payment of a €10 ($13) medical fee from the city clinic where her son died, Sauerland commented: "I am sorry something like that happened. We wrote letters of condolence, but they weren't forwarded. We don't have the addresses and if we don't receive them from the state authorities, we can't establish contact."

The Love Parade took place at a fenced-in site for the first time in its history, with a tunnel and a ramp acting as entrance and exit simultaneously.

"The access route through the tunnel and ramp was checked," said Sauerland, although Spiegel Online put it to him that the evidence didn't show anything about a precise inspection.

However, he referred to various checks with police and security teams. "No other Love Parade -- I believe -- was ever prepared so intensively, with so many [internal] reports and external assessments, as the one in Duisburg," said the mayor. "But we are currently out a process of clarifying the events. This review is being carried out by an external law firm and will be complete in about two weeks. We will make the findings available to the [parliamentary] internal affairs committee, the public prosecutor's office and of course also the city council and thus the public."

Despite reports of 1.4 million people at the event, Sauerland conceded to Spiegel that this was a "marketing lie."

"There were the numbers in the millions, for the media, which came from the event organizer, Lopavent," he said. "Then there were the real numbers for our planning purposes. We looked at past Love Parades, analyzed the anticipated number of visitors and issued a permit for a maximum of 250,000 people. There were just inflated numbers, used for marketing purposes and nothing else. The same thing has been done with many other events, for example with the Love Parades in Dortmund and Essen."

Spiegel Online also quizzed the mayor about whether he would resign, pointing out that the German president had indirectly called for him to leave office.

"I will confront that responsibility once everything has been clarified," said the mayor. "Let's continue that conversation when the process of investigation the event is complete."

He concluded: "The city of Duisburg will still exist after this event. And unless something drastic happens, my life will still exist after this event. Neither can function properly until we have clarified everything. When we know that and have a clear view, we will be able to pass final judgment."