WARSAW (Reuters) - One miner was confirmed dead after a tremor at the Borynia-Zofiowka coal mine in Poland, and rescuers are still trying to reach six more underground, mine owner JSW said.

       The tremor shook the mine in southern Poland on Saturday morning. There were 52 workers in the area, 42 got out on their own, and 10 remained underground.

       After many hours, rescuers reached four miners late on Saturday but they did not show any signs of life, JSW said.

       "The first victim in Zofiówka. Rescuers transported one of the four miners found .... The miner was transported to the rescue base, where the doctor declared his death," JSW said in a statement published at night.

       This is the second accident in a coal mine owned by JSW. On Wednesday, five people died and seven were trapped in the Pniowek coal mine in southern Poland after an explosion.

       (Reporting by Pawel Florkiewicz; Editing by Kim Coghill)