An unspecified safety problem prompted an emergency shutdown at a Russian nuclear power plant, federal officials said Tuesday. Radiation levels in and around the plant were normal following the incident at the first unit of the Balakovsky plant, which occurred around 11:15 p.m. (2015 GMT) Monday, the Emergency Situations Ministry said. The plant is located near the Volga River city of Saratov, about 700 kilometers southeast of Moscow. "Initial reports indicate the cause of the shutdown was a problem with the safety system. The reactor has been taken off-line," a ministry statement said. Russian lawmakers recently passed legislation to restructure the country's nuclear power sector, which includes 31 reactors at 10 nuclear power plants, accounting for around 17 percent of electricity generation. President Vladimir Putin has pledged to build another 42 atomic reactors by 2030 and increase the percentage of electricity generation produced by nuclear plants to about one-quarter.