KIEV — The Zaporizhzhia nuclear power plant in southern Ukraine has been entirely shut down, Ukraine’s state-run nuclear energy operator Energoatom said on Sunday.

The functioning of the plant halted after the last power unit No 6 was disconnected from the power grid at 3:41 am local time (0041 GMT) on Sunday over safety concerns, Energoatom said in a report on Telegram.

The report said preparations are underway to cool the unit and switch to a cold state.

Energoatom has called for establishing a demilitarized zone around the plant, allowing for repairs and resumption of safe operations.

Zaporizhzhia, one of Europe’s largest nuclear power plants, has been controlled by Russian forces since early March, while its Ukrainian staff continued to operate it.

In recent weeks, the site of the plant has been attacked by shelling, sparking international concerns about its safety.