Police in Derbyshire, England have dyed a blue "lagoon" black in a bid to deter people visiting "the picturesque location" during lockdown.
Buxton Police said in a post on social media that the move was a response to reports that people had been gathering at a disused quarry known as the "Blue Lagoon".
Like Australia, the UK is on lockdown to help prevent the spread of the coronavirus, with residents permitted to leave their homes only to visit the supermarket, attend to medical needs, work if it cannot be done from home, and to exercise.
"With this in mind, we have attended the location this morning and used water dye to make the water look less appealing," police said.
"This is a regular tactic that we use to reduce ASB [antisocial behaviour]... However, as things stand, it has never been so important to discourage these types of gatherings."
A 2013 BBC report said the quarry at Harpur Hill had been dyed black in an effort to prevent people from swimming in it.
Signs warn would-be swimmers that the water contains rubbish and dead animals and could cause skin complaints.
The water has a pH level of 11.3, not much lower than that of bleach, which has a 12.3 pH level, the report said.
Still, "dozens of people still swim there".
One commenter on the Buxton Police post described the quarry as "toxic".
"I used to live on the road with the entrance to this and every summer we had people from all over the country visit. It burns your skin, if you swallow any you will be sick. Do not go anywhere near it."
Another said: "one of my sons went in there years ago and he had skin irritation problems for months after."
While most commenters seemed to support the move, some said the post had inspired them to visit the quarry.
"Looks lovely and never knew it existed," one person said. "Might head up with the dogs this weekend, so boring stuck in the house."