KYIV, Ukraine (AP) — A team of international nuclear inspectors was heading Wednesday to the Zaporizhzhia nuclear power plant caught in the middle of the fighting in southern Ukraine amid international concern of a potential accident or radiation leak.

Rafael Grossi, the head of the the International Atomic Energy Agency, said he hoped to establish a permanent mission in Ukraine to monitor Europe’s largest nuclear plant.

“These operations are very complex operations. We are going to a war zone. We are going to occupied territory. And this requires explicit guarantees from not only from the Russians, but also from the Republic of Ukraine,” Grossi said in the Ukrainian capital of Kyiv before the monitoring the mission’s departure.

“We have been able to secure that. … So now we are moving.”

The power plant has been occupied by Russian forces and operated by Ukrainian workers since the early days of the 6-month-old war.

The site was recently temporarily cut off from the electrical grid because of fire damage, causing a blackout in the region and heightening fears of a catastrophe in a country haunted by the Chernobyl disaster.