The International Atomic Energy Agency says it has been informed by the Zaporizhzhia nuclear power plant in southeastern Ukraine that a drone has struck a turbine building at the site, causing a hole in its wall.
IAEA chief Rafael Grossi expressed serious concern about the reported incident and said "Attacking nuclear sites is like playing with fire".
The IAEA's team at the Russian-held power plant has requested access to examine the affected turbine building first-hand, the agency said in an X post.
Earlier, Russia's state-owned nuclear energy company Rosatom says a Ukrainian drone had struck the Russian-controlled Zaporizhzhia nuclear plant, Europe's largest, causing no damage to key equipment but the Ukrainian military denied it.
Rosatom's head Alexei Likhachev called the incident "deliberate" and said it left a hole in the wall of a turbine hall.
"This afternoon, a Ukrainian kamikaze combat drone struck the turbine hall building of Power Unit No. 6, resulting in a subsequent detonation," Likhachev said in a statement.
"The explosion caused no damage to the primary equipment; however, it tore a hole in the turbine hall wall."
Ukraine's military denied the Russian claims as "yet another propaganda ploy".
It said that the Ukrainian troops did not strike power unit No 6 at the Zaporizhzhia nuclear power plant.
"Ukrainian servicemen act strictly within the international humanitarian law and are fully aware of the consequences of any actions targeting nuclear facilities," the military said in a statement.
"At the relevant section of the front line, there was no active fighting during the incident and no weapons were used."
with AP and DPA