Civil liberties and privacy campaigners say that more than £3.9 million has been spent by public bodies across the country in the last two years on paying private investigators for surveillance work - including snooping on their own staff.
The Big Brother Watch study found 27 local councils nationally had employed private firms to undertake surveillance - ten of which are in London.
Hammersmith & Fulham
Kensington & Chelsea
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A 24-year-old man has been arrested on suspicion of murder after the body washed up on the Thames shoreline.
Seven people have now been arrested after a man died from serious head injuries
The 38-year-old officer was on his way home from a night shift when he collapsed. His death is not being treated as suspicious.