Two security guards are in a critical condition in hospital after they were seriously injured in an explosion at an ex-colliery.
The two men, aged 38 and 26, suffered serious facial burns in the blast at the former Welbeck Colliery site, near Meden Vale, in Nottinghamshire yesterday.
They have not yet been identified but are being treated in the Queen's Medical Centre, Nottingham, where they are both said to be in a critical but stable condition.
A spokesman for Nottinghamshire Police said: “It is understood that the men were working at the site as security personnel.”
He added: “Detectives are liaising with the site owners, UK Coal, with the Fire Service and the Health and Safety Executive to determine the sequence of events leading up to the incident.”
The explosion was reported at around 7.30pm yesterday and involved an electrical sub-station above the ground.
A spokeswoman for Nottinghamshire Fire and Rescue Service said the explosion was from an electrical component in the 40m x 30m single-storey building.
She added: “The fire itself was very small. The main issue was the explosion itself and the two people injured.
”Investigations are ongoing.“
According to UK Coal, the Welbeck site has not been a working colliery since May 2010.
Shafts have been filled and a small team has remained on site decommissioning the mine which has exhausted three seams of coal since work on sinking the twin shafts began in 1912.
In its heyday, Welbeck employed around 1,400 miners and had an annual output of around 1.5 million tonnes.
A spokesman for UK Coal said it was thought the two security guards were the only people on site at the time of the explosion and they called the emergency services in the aftermath of the blast.
A statement from UK Coal said: ”There has been no mining at the colliery since it was closed in May 2010, following which all of the underground shafts and workings have been sealed and closed.
“The electricity substation is situated on the surface and supplies both the site and surrounding area when required.
”The two injured men were not UK Coal employees, but were contracted to be working as security guards on the site.
“UK Coal continues to help the police and HSE investigations.”