Birmingham police have warned against attending illegal raves as the city teeters under the threat of a localised lockdown.
Drone footage of revellers gathering in a car park was released on Friday by West Midlands Police.
The city, the second largest in England, has seen a sharp rise in coronavirus infections in recent weeks.
A statement from the force said: “Birmingham has seen a rise in COVID-19 cases and the city faces the prospect of being [the] subject of a localised lockdown.
“But despite the clear public health warnings people continue to put themselves and others at risk by gathering at illegal raves - as our drones captured last weekend.
Hundreds of people congregated shoulder-to-shoulder at this unlicensed music event staged in a Birmingham car park.
The statement continued: “[These events] are unacceptable at any time but even more so during a pandemic in which large gatherings are banned to help stop the spread of a killer virus.
“There are no safety measures in place at these unauthorised events. If anything goes wrong and you, or your son or daughter, are attending, the emergency services might not be able to help you as quickly as normal.
“We are sending a strong warning to anyone who is found organising these kind of events faces the prospect of us seizing equipment and prosecution.”
The force warned that officers would be acting on intelligence to stop and disperse any future gatherings, while also monitoring for other criminal behaviour - such as disorder, selling drugs and possessing weapons.
Chief Superintendent Claire Bell said: "It’s important everyone realises the dangers of these illegal events.
"There is a danger to your own and loved ones health, but also from other criminal activity they may attract. You could end up seriously injured, ill or with a criminal record.
"We know how difficult it’s been with restrictions and we’ve always said we’ll try and engage and educate people around Government guidelines. But there can be no excuse for organising an illegal rave which then encourages and tempts others to attend.
"We’ll be seeking to not only seize equipment, but take enforcement action against those who arrange such events. We really need everyone to be responsible to help us get through this pandemic."
Bell said the force were urging people to inform them if they hear of plans for large gatherings by calling 101.
Elsewhere, police in Manchester were dispatched to 40 house parties on Thursday evening despite coronavirus restrictions, with one seeing an officer suffer a broken jaw.
Much of Greater Manchester is already subject to a localised lockdown, with many fearing the city centre could be next to follow if restriction measures are not followed.
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