London (CNN) -- A third miner was found dead Friday in a flooded mine in Wales, police said.
The search continues for the one man still missing after four miners became trapped in the Gleision Colliery, in the Swansea Valley, early Thursday.
Authorities have identified the four men involved as Phillip Hill, 45, from Neath; and Charles Breslin, 62, David Powell, 50, and Garry Jenkins, 39, from the Swansea Valley.
Police have not yet confirmed the identity of the three men found dead. They said the families of the four men had been informed.
Only one body has so far been brought to the surface, police said.
Three other miners escaped Thursday, including one who was hospitalized.
Specialist mine rescuers, police, fire and ambulance teams were working at the drift mine Friday.
First Minister Carwyn Jones, who leads the Welsh government, paid tribute to the efforts of rescue workers at the scene and to those who have lost loved ones.
"My thoughts and deepest sympathies are with all of the families as this horrifying news filters through," he said.
"The people of Wales, and indeed people across the world stand together in solidarity with the families through this terrible tragedy."
The British government will carry out a full investigation into the incident, Welsh Secretary Cheryl Gillan said in a statement released Friday.
Rescue officer Andrew Watson told CNN Thursday that water was believed to have rushed into the mineshaft where the men were working when they broke into a neighboring abandoned mine.
Pumps are being used to reduce the level of the water, he said.
As of June 2011, 1,500 people in Wales worked in the mining industry. according to government figures.
In a drift mine like the one where the men are trapped, coal is excavated from the side of a hill using shafts that are almost horizontal.
CNN's Laura Perez Maestro and Laura Smith-Spark contributed to this report.