Experts from the National Grid are trying to find out what caused an explosion at the five-star Churchill Hyatt Regency hotel in central London.
The London Fire Brigade is also carrying out a probe into the blast, which is thought to have happened because of a gas leak.
A total of 14 people suffered injuries in Friday’s incident at the top hotel, which is located in Berkeley Mews, close to Marble Arch.
Five of them had to be taken to hospital while the road was closed in both directions throughout the day.
On Monday morning rubble and broken glass was still lying on the ground in the area.
The Churchill Hyatt Regency, which describes itself as “one of the finest five-star hotels in London”, has been completely evacuated, with all guests being moved to alternative accommodation.
The hotel has a total of 434 rooms, with rates averaging at £264 per room per night.
A hotel spokesman said they would release a statement at a later date.
Jeanette Unsworth, spokeswoman for the National Grid, said investigations are still ongoing as the firm had to make sure “the situation was safe”.
The National Grid was only able to begin its probe after the emergency services had rescued everyone who was injured in the incident, she added.
She could not say what had caused the explosion or how long the investigation would take.
‘Chaos’ at reception
A spokesman for London Fire Brigade also said that the blast is still being investigated but was probably due to a suspected gas leak. He added that duty of care was now back with the hotel.
Hotel guest Raymund Reyes, 40, said that he was making a phone call to his wife when the explosion occurred.
He said the floor started to shake and the power went out, meaning it was “pitch dark”. Mr Reyes then went into the hallway before making his way down to reception, where he said the scene was “chaos”.