Media playback is unsupported on your device Media caption Supt Phil Davies confirmed one miner had been found dead

A rescue operation is continuing to reach three miners trapped for more than 24 hours in a Swansea valley colliery, while the body of a fourth has been located.

The men became trapped 90m (295ft) below in the flooded Gleision Colliery near Pontardawe on Thursday morning.

They are: Charles Breslin, 62, David Powell, 50, Garry Jenkins, 39, and Phillip Hill, 45.

Emergency workers have identified the body and relatives are being informed.

Meanwhile, rescuers have found no methane and oxygen levels are reported to be good.

The dead man, whose body has still not been recovered, was located by rescue crews in a very deep part of the flooded mine at Cilybebyll earlier on Friday.

Welsh Secretary Cheryl Gillan told BBC Wales News website reporter David Dulin at the scene that she will be calling a civil contingency meeting in the cabinet office.

She said Prime Minister David Cameron had been in contact while on his way back from Libya.

Neath MP Peter Hain there was some relief after rescuers discovered there is no methane down below and oxygen levels are good in the area where it is hoped the men have scrambled to.

But he said: "We still don't know where the trapped miners are.

"The rescue workers are right down to the sump at the bottom which shows the remaining three miners are not in that area so must have been trying to get back into the old workings to escape the existing mine.

"The good news is oxygen is circulating in the mine and the old mine workings, creating a circular supply of air."

Flood water

Two miners managed to escape as the flood water engulfed the drift mine when a retaining wall holding back a body of water underground failed on Thursday.

They are assisting rescuers.

A third is in Morriston Hospital, Swansea but not believed to be as seriously ill as previously thought.

David Dulin, BBC Wales News website reporter, at Rhos Community Centre At around 12:40 BST a small group of men briefly gathered at the back of the community centre and hugged each other before going their separate ways. More people then came out from the centre and stood motionless. Throughout the morning rescue workers have been coming and going at the centre. Volunteers have been bringing food and drink for the families and the rescue teams throughout the morning.

Families and friends who are at the nearby Rhos community centre are being kept informed of developments.

First Minister Carwyn Jones said the focus is on getting the men out alive.

He said: "There are four groups of people in there waiting to hear the fate of their loved ones. It's a very, very difficult time.

"They have a lot of support, not just from Wales but around the world. Until we know the outcome, it's always going to be very difficult."

Asked about health and safety, he added: "Let's see if we can get these miners out alive, the focus has to be on that. An investigation can come after."

"All I wanted to do is come here and chat. The real work is being done at the Gleision mine. To think of a mining accident happening now is difficult to imagine."

Chris Margetts, from Mid and West Wales Fire and Rescue Service, said the dead miner was found on the "exit side" of the water and that it was "quite possible the team has been split".

Emergency services said they had not given up hope of finding the other three men alive and hope they have found their way in to an air pocket on the other side of the water.

Earlier, speaking to BBC Wales news website reporter David Dulin, Mr Hain said the mood at the community centre was "very sombre and down".

He said: "I've spoken to all the relatives and they are going through a nightmare which none of us can comprehend.

He said the rescue workers were hoping to recover the body within the next couple of hours so he could be formally identified.

The alarm was raised at 09:21 BST on Thursday and members of the Mines Rescue Service, together with specialist divers, helpers from all over the country and the fire service, have been working through the night.

They were forced back during the night after debris made the water too murky.

Fresh rescue teams were brought in on Friday to relieve crews.

An expert listening device, which can detect movement deep underground, is the among the specialist kit being used.

'Working very hard'

Mr Margetts said it was a very "delicate" operation as care had to be taken not to damage the mine's structure. But he said the water levels are receding. Pumps are continuing to remove water from the mine and oxygen is being pumped in.

He said the rescue crews have now gained enough access to get teams down in wetsuits to start the excavation process.

They are continuing to pump out water, excavating the blockages and shoring up the tunnels.

"It is slow and it is steady, but as we're aware with previous incidents, these incidents take time," he said. "We need to do it properly.

"Everyone is working very hard, we just need a little bit of luck."

Gleision Colliery, in operation since 1993, works coal under a very steep hillside above the banks of the river Tawe.

It is a small drift mine working a coal seam from the Rhondda in a remote location cut into a hillside in the Swansea Valley.