An inquiry has been launched after four men died in a mining tragedy that "stabbed through the heart" of a community.

The bodies of Phillip Hill, Charles Breslin, David Powell and Garry Jenkins were discovered at the Gleision Colliery in south Wales on Friday, dashing desperate hopes that any of the men would be found alive.

Authorities will now switch from a search and recovery operation at the flooded mine to an investigation into the incident, police said.

Police described the sad conclusion to the rescue efforts as "the one none of us wanted".

The alarm was raised early on Thursday after the shaft flooded, trapping the men. It had been hoped that the miners - originally part of a group of seven - might have found refuge in an air pocket following the accident.

The bad news came through gradually on Friday however, with police announcing at 6pm that the body of the last of the four had been found at the pit near Swansea.

Peter Vaughan, Chief Constable of South Wales Police, said: "We've tried to bring this safely to its conclusion. Unfortunately the conclusion we have is the one none of us wanted." Expressing his condolences to the men's relatives, he said: "I can't begin to imagine what the families are going through."

Fire and rescue and ambulance workers said they had never seen or worked in such conditions before. The men's bodies were found close together, one on the exit side of the blockage and the other three, which were recovered on Friday afternoon, in the area where they had been working.

The tragedy sent shockwaves through the close-knit Swansea Valley community, which had been desperately hoping that the last man would be found alive. Mr Vaughan said: "We've been humbled by the community spirit that's been shown during this most tragic of incidents."

And he asked for the privacy of the families of Mr Hill, 45, from Neath, Mr Breslin, 62, Mr Powell, 50, and Mr Jenkins, all from the Swansea Valley, to be respected.