Stockholm - A fire that broke out Friday on the roof of Sweden's Ringhals nuclear power plant was put out safely, local fire control authorities said.

According to the report, the fire started at the plant's second reactor when roofers working with gas-fuelled torches inadvertently set roofing materials on fire, the report said.

The automatic alarm for the plant, located south of Gothenburg on Sweden's west coast, was triggered after heavy smoke developed.

Sweden's three nuclear power plants - Ringhals, Forsmark and Oskarshamn - have repeatedly been in the news in recent years due to safety lapses and a number of accidents.

The Ringhals plant, with a yearly energy capacity of 3,662 megawatts, contains four reactors and is the largest nuclear power plant in northern Europe. (dpa)