A drone strike close to the Zaporizhzhia Nuclear Power Plant in occupied southeastern Ukraine has killed one nuclear specialist and wounded 17, according to Russian reports.

Moscow asserted on Tuesday that the drone was launched by Ukraine. The security of Europe’s biggest nuclear plant has provoked significant global concern amid the full-scale war on Ukraine that Russia launched in February 2022.

Most of those injured by the strike were employees of the plant, according to a Telegram update by the Russian management of the nuclear facility. It asserted that the attack constituted one of the most serious incidents in the plant’s history.

The International Atomic Energy Agency (IAEA) earlier confirmed reports that the strike hit staff members at a bus stop.

“No nuclear safety or security damage was reported,” the IAEA, the United Nations’ nuclear watchdog, said on social media.

However, it called “on military commanders responsible for these actions as well as all others aiming on nuclear power plants and/or their staff to put an immediate stop to these unacceptable actions”, citing the “great risks to nuclear safety”.

The Zaporizhzhia plant was seized by Russian forces a month after Moscow launched its invasion. The facility has been under Russian management since.

The safety of the plant – and the potential consequences of a hit amid the hostilities – have been a concern since the start of the war.

Zaporizhzhia’s six reactors can produce nearly six gigawatts of electricity, and the plant was crucial to supplying power to Ukraine’s national grid. All of the reactors have been shut down since Russia captured the plant, but a strike could cause damage and potentially cause serious leaks of radioactive material.

Tuesday’s strike came ahead of a scheduled visit by IAEA Director-General Rafael Grossi to assess nuclear safety. It’s not clear if that visit will still take place.

A Russian strike on a thermal power plant was reported in central Ukraine a few hours later, forcing a halt to operations, according to DTEK, Ukraine’s largest energy provider and the company that operates the plant.

No casualties were reported, but DTEK stated on social media that the attack caused “significant damage to equipment”.

Russia has attacked the company’s thermal plants 230 times since the start of the war, according to DTEK’s Telegram channel, as it wages a campaign to destroy Ukraine’s energy infrastructure.