At least eight miners were dead, two missing and a handful injured after an explosion at a mine in far Northern Russia, latest in a series of explosions that have killed over 150 Russian miners since March, reports said Tuesday, according to dpa. The methane-gas explosion occurred late Monday at the Komsomolskaya mine 1,900 kilometres north-east of Moscow. At the time, 277 workers, including 18 in the blast area, were in the mine 100 kilometres north of the Arctic Circle near the city of Vorkuta. By Tuesday evening, eight bodies had been pulled from the collapsed shaft, with two miners missing and three injured, Russia's Emergency Situations Ministry said. A day of mourning was declared for Friday in Vorkuta, Mayor Valery Budovsky told media. He said the city would provide assistance, inclulding material help, to families of the deceased. While the blast 800 metres below ground is said to have been the result of methane gas, the exact cause of the accident was not immediately clear. Officials said a special committee had been formed to study investigate the accident. "All versions of what happened are being studied simultaneously. It's still early to comment on the accident," Konstantin Pulikovsky, head of Rostekhnadzor, the federal agency responsible for mine safety, said in a statement. Pulikovsky and other officials stressed that "the most important thing now is to find the three remaining miners," adding that approximately 40 rescue workers were racing against the air and water rushing into the fragile mine. The blast came amid a string of mine-related tragedies that have killed well over 150 in the last three months. Little more than a month ago, a methane explosion killed 38 in Siberia's Kemerovo region and in March another methane-gas blast took 110 lives at a nearby mine. Calls for accountability and a system overhaul have come from the country's highest-ranking politicians, including Prime Minister Mikhail Fradkov and Boris Gryzlov, speaker of the lower house of parliament. With world commodities prices consistently rising, officials have cited a "race for profits" as culprit in the numerous explosions. Prosecutors in Vorkuta, which is in the remote Komi republic, opened a criminal case on charges of "a violation of safety rules during mining work leading to the death of two or more people." Vorkutaugol, the mine's owner, denied any safety violations. "(We) in the company follow that question very seriously, it's our value," Svetlana Tsarionova, a company spokeswoman, told Interfax. The company spent 640 million rubles (24.7 million dollars) on safety last year and was set to spend 840 million rubles this year. Many of Russia's mines date back to Soviet times, however, and the accidents have not been unique to this spring and summer. In 2005, 25 people died in a single mine explosion, and 47 perished in a blast in 2004. In 1997, the final toll of an explosion was put at 67, but the March explosion is thought to be the most deadly. That explosion and the May explosion led to the immediate closing of dozens of Russian mines where safety violations had been revealed, though many have since reopened after addressing the citations.