The Blue Lagoon near Buxton, a flooded quarry - has inviting turquoise waters, but it is so polluted it's almost as toxic as bleach.
There are warning signs saying it can cause skin and eye irritations and stomach problems, but families and young swimmers are ignoring them.
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A gunman who held two members of staff hostage at a bowling alley in Nuneaton has been arrested.
There are reports of flash-bangs being used at Bermuda Park as ambulances arrive at the scene.
Chris Turner, an eyewitness to the incident at Bermuda Park, said a man was carrying a shotgun and told him to "get out of the way".