The Callaway nuclear plant is now out of service after a small fire broke out late Friday night. The Callaway Energy Center declared an “unusual event” when a fire broke out in the turbine building. Crews extinguished the blaze in the non-nuclear part of the building, but shut down the facility because of safety reasons.  Officials are determining when the plant can be operational again. Ameren Missouri and the U.S. Nuclear Regulatory Commission (NRC) have started an investigation into the cause of the fire.

No one was injured and the fire didn’t threaten the public or any nearby communities. According to a press release from Ameren: “The term ‘Unusual Event’ was established by the NRC to describe a relatively minor occurrence a nuclear power plant that could reduce the overall level of safety. During such an event, no public action is advised or necessary.”

The plant produces about 20 percent of electricity Ameren supplies to customers. While it’s out of service, other plants will provide that energy.

This is the second incident at the plant in recent months, back in April an explosion injured three workers. Ameren said that explosion came from an electrical flash in the switch yard area, but did not affect the operations of the nuclear plant.