Reports suggest people were playing on ice at a park near Birmingham, the fire service says.
Image source, PA MediaA search and rescue operation is under way after police said a number of people pulled from a lake near Solihull in freezing temperatures are in a critical condition.
Reports suggested people had been playing on the ice at Babbs Mill Park and fell through, according to West Midlands Fire Service.
It said people had received treatment before being taken to hospital.
Specialist teams and equipment are involved in the search.
The fire service said they were called shortly after 1430 GMT on Sunday.
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Concerned members of the community gathered near the scene in what is residential area, as emergency services carried out work at the lake.
A drone was also spotted flying over the water, the BBC’s Sophie Madden said, reporting from the scene.
It was likely that the emergency service presence would remain there for a number of hours,she added.
Babbs Mill Park is a local nature reserve with a lake, river, wildflower grasslands and woodlands.
Temperatures of 1C (34F) were reported in the area at the time the emergency services were called. They are expected to plummet to -3C during the night.
The incident came as police in Cumbria said they were dealing with an “incident” at Siddick Pond in Workington.
The Met Office warned of the dangers posed by ice.
A spokesperson said: “With temperatures set to struggle to get much above freezing over the coming days across much of the country, stretches of water such as rivers and ponds are at risk of freezing.
“While frozen rivers and ponds can be fascinating, they can be dangerous and a hazard to life.”
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