A Ukrainian nuclear plant was hit by a Russian “projectile” but the building that was hit was not part of the reactor, the head of the United Nations’ atomic energy has said.

Earlier reports conflicted over what part of the plant was affected by a fire.

Nuclear plant spokesman Andriy Tuz told Ukrainian television that shells fell directly on the facility, and set fire to reactor that is not operating and to an administrative training building.

International Atomic Energy Agency director-general Rafael Mariano Grossi said on Friday that the building hit was “not part of the reactor”.

He said that the Ukrainians are still in control of the reactor.

He added: “What we understand that this projectile is coming from the Russian forces. We do not have details of what kind of projectile it is.”

He said there has been no release of radiation and that the fire had been extinguished.

He said two people on the site were injured in the fire.

He said that only one reactor is operating at about 60%.