A tank battalion mutinied Tuesday at a Georgian military base near the capital and several hundred army personnel were refusing to follow orders, Defense Minister David Sikharulidze said. The mutiny followed an announcement by the Interior Ministry that it had uncovered a Russia-supported plot to overthrow the government and had arrested the suspected organizer. Interior Ministry spokesman Shota Utiashvili said the suspected coup plot was organized by a former special forces commander, Georgy Gvaladze. Gvaladze and an army officer on active duty have been arrested, the spokesman said. The coup plotters, backed by 5,000 Russian troops, were planning to disrupt NATO military exercises set to begin Wednesday in Georgia, Utiashvili said. Sikharulidze said he had been blocked from entering the military base in Mukhrovani, about 20 miles (30 kilometers) from Tbilisi, the capital. Among the mutineers were civilians who had no relation to the battalion, he said.