Police have warned young people not to attend illegal raves this weekend, promising a tougher approach after two “quarantine raves” attracted 6,000 people last Saturday. Greater Manchester police (GMP) said intelligence failures meant they were unable to prevent a dance party attended by 4,000 people in a country park in Oldham last weekend. A 20-year-old man died of a drug overdose at that event, and a woman was raped and three men were stabbed at a separate illegal rave in Trafford. Andy Burnham, the mayor of Greater Manchester, said police would take a “stronger, more robust and interventionist” approach, and people would face fines “or something much more severe” if they attend future mass gatherings during the coronavirus lockdown. Police said they believed there were “elements of organised crime” behind such events, which are arranged on social media with tickets reportedly sold for up to £30. The location of the rave is not revealed until the last moment and drugs are widely available. An investigation is ongoing into the identity of the organisers of last weekend’s raves but no arrests have been made. Police said they had intelligence that further events were being planned for this weekend. Burnham said last Saturday was “one of the most difficult days in policing we’ve had in recent times” as the force contended with several serious incidents as well as the two mass raves and a confrontation between self-styled “statue protectors” and Black Lives Matter protesters in Bolton. He said there were lessons to learn from failures in GMP’s intelligence gathering and its communication with local councils over the 4,000-strong rave at Daisy Nook country park. Nick Bailey, GMP’s assistant chief constable, admitted the force did not respond promptly enough to stop the gathering. He said his officers failed to find the exact location of the rave despite several attempts to do so. It also emerged that local councillors had been told the event had been “stood down and wasn’t something to worry about” before the crowds arrived. The force has put a “silver command” structure in place led by senior officers in anticipation of further events this weekend. Bailey appealed to parents to pass on any information about future raves to police. “Please, please, if you know about these events then make sure you are telling the authorities, make sure you are telling Greater Manchester police, so we have the best opportunity to prevent them from occurring,” he said. Beverley Hughes, Greater Manchester’s deputy mayor for policing, said the events were a “complete free-for-all for serious criminals” and “very dangerous and completely unregulated”. “We will bear down now, this weekend and beyond, with everything we’ve got across the police and our local agencies to try and stop any repeat attempts of this,” she said. “The last thing we want is a summer of raves.”