Westminster City Council, which has responsibility for the pop-up toilets in the area, said its “deepest sympathies are with Mr Holding’s family and friends following his tragic death”.

An HSE spokesperson said: “We understand the family’s concerns and while we are still investigating the incident, primacy remains with the Metropolitan Police. Inquiries at our specialist site in Buxton are ongoing.

“We are committed to maintaining regular contact with Mr Holding’s family in line with this police-led investigation. Our thoughts remain with them at this difficult time.”