The Independent Police Complaints Commission says it will be looking into whether police officers should face criminal investigation after the death of 39-year-old Leon Briggs in custody.
At this stage we believe there is an indication that potential criminal offences may have been committed including gross negligence and/or unlawful act manslaughter, misconduct in public office, and/or offences under the Health and Safety at Work Act 1974".
"We will also be considering whether any potential disciplinary offences have been committed."
More top news
Icy stretches will form tonight as temperatures drop and wintry showers develop later.
A woman has been banned from keeping all animals for three years after admitting neglecting her cat and four kittens - two of whom died.
With the cold weather expected to last for at least the next five days, the Met Office has issued various snow and ice warnings.