Rescuers bored passages to a flooded coal mine in southern Russia in a frantic attempt to save 46 miners trapped for more than a day by freezing water. Bulldozers and trucks dumped concrete slabs, metal rods and rocks into the main shaft of the Zapadnaya mine in the Rostov region to try and stop icy water from filling any more galleries more than 700 meters (230 feet) below the surface. From a neighboring mine, miners began to hollow out a passageway to a location where their 46 fellow-workers could have taken refuge from numbing water that rushed into Zapadnaya Thursday afternoon. But the fate of the 46 remained unknown. Authorities still had not established contact with them late Friday and could only guess if they were still alive and if so, where they had taken refuge. More than 24 hours after icy water first gushed into the mine where 71 men were working underground, the chances of rescuing those still trapped lessened by the minute. "There is still a chance to save them... God willing 50 percent," Igor Kulikov, a miner who managed to scramble out, told Russian television. Others said that some of the shafts in Zapadnaya ran at an angle and that the trapped men could survive for several days if they had managed to reach these. But the authorities had no clue to the location of the victims. They also reported hearing sounds of what appeared to be a cave-in in the mine on Friday evening. The frightening noises prompted rescuers to order two men to go down the mine overnight in a special elevator to investigate what may have happened. "I do not estimate what our chances are of finding any survivors -- we are doing what we can to save them," Kiril Zhitinyov, spokesman for the Rostov Governor Vladimir Chub, told AFP. Twenty-five miners who managed to reach the surface described the numbing water rushing in as a "roaring current." "We barely got out of there," Kulikov told Russian television. "The people who were in the lower levels got trapped." "The water flooded in without warning," said Konstantin Koreoshenko. "All of a sudden, we were up to our necks in water. It knocked you off your feet." Anxious relatives rushed to the mine headquarters to scour the typed posted lists of those down the mine at the time of the accident and of those who had managed to escape. Some sat quietly, their faces tense, some wiped away tears. Among those trapped was Vasily Avdeev, appointed director of the mine only days ago, according to RIA Novosti news agency. The accident was the second one at the mine this year, ITAR-TASS reported. Water flooded the mine in February but there were no people underground at the time, the news agency said. Russian President Vladimir Putin has been informed of the accident and local authorities have launched an investigation into its cause, news reports said. A group of rescuers, including divers, arrived from Moscow in the region and were shortly expected to arrive on the scene near the town of Novoshakhtinsk. Mines in Russia are notorious for their poor safety record, and fatal accidents are common. **PHOTO CAPTION*** Russian miners take a break. (AFP/EPA/File/Ilya Pitalev)