The government has been cracking down on unregulated mining operations, which account for almost 80 percent of the country's 16,000 mines. The closure of about 1,000 dangerous small mines last year helped to cut in half the average number of miners killed, to about six a day, in the first six months of this year, the government has said. Major gas explosions in coal mines remain a problem, though the number of accidents and deaths have gradually declined year by year, the chief of the State Administration of Work Safety, Luo Lin, told a national conference in September.[59]