KIEV, Ukraine (AP) _ Power output was halved Sunday at reactor No. 2 of Ukraine's Rivne nuclear power plant to conduct repairs, officials said.

The measure was taken after one of the reactor's generators was stopped to fix a cavity discovered in its piping and to investigate some vibrations in bearings, the Emergency Situations Ministry said.

No radiation leaks were reported.

The Rivne plant, 200 miles northeast of the capital Kiev, has three Soviet-designed light-water reactors.

Ukraine's five nuclear power plants, with 14 working reactors, produce more than 40 percent of the electricity consumed in the former Soviet republic.