The worker has been freed by rescuers but has serious crush injuries, the Met Police says.
Image source, Tim Stokes/BBCA man has been crushed and trapped underneath a telescopic public urinal while working on the device in central London.
A rescue operation is in place at the junction between Shaftesbury Avenue and Charing Cross Road.
The man was working at the site at Cambridge Circus and has been seriously injured, the Met Police said.
Police, fire crews, paramedics and air ambulance workers were sent to the scene at 13:05 GMT.
The man is trapped underneath the hydraulic urinal, a pop-up toilet stored beneath the ground which is brought to street level at night for people to use.
Image source, Keto Cancer Queen
A London Ambulance Service spokesperson said: “We sent a number of resources to the scene, including an ambulance crew, members of our hazardous area response team (HART), members of our tactical response unit and a medic in a fast response car.
“We also dispatched London’s Air Ambulance.”
Four fire engines and around 25 firefighters from Soho, Euston and Dowgate fire stations are at the scene.
A spokesperson for the Met Police confirmed the man is thought to have sustained crush injuries while working on a telescopic urinal at the location.
Roads going through Cambridge Circus have been closed.
The incident is ongoing.
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