Vienna, April 10 : International Atomic Energy Agency (IAEA), the United Nations nuclear watchdog, has said that the drone attack at the Zaporizhzhia nuclear power plant (ZNPP) in Ukraine on Sunday is a "serious incident that endangered nuclear safety and security".

Director General of the IAEA Rafael Mariano Grossi on Sunday night urged military decision-makers to abstain from any action violating the basic principles that protect nuclear facilities.

He said that such "reckless attacks significantly increase the risk of a major nuclear accident and must cease immediately".

For the first time since November 2022, Europe's largest nuclear power plant was directly targeted in military action that also represents a clear violation of the five basic principles for protecting the facility established by Director General Grossi at the United Nations Security Council in May last year, the IAEA said in a statement.

At this point, there are no indications of damage to critical nuclear safety or security systems at the site. However, the military strikes were another stark reminder of persistent threats to the ZNPP and other nuclear facilities during the armed conflict, despite the IAEA's efforts to reduce the risk of a severe accident that could harm people and the environment in Ukraine and beyond, it added.

"The IAEA experts stationed at the site went to three affected locations and were able to confirm the physical impact of the drone detonations, including at one of the site's six reactor buildings where surveillance and communication equipment appeared to have been targeted. While they were at the roof of the reactor, unit 6, Russian troops engaged what appeared to be an approaching drone. This was followed by an explosion near the reactor building," the UN nuclear watchdog stated.

"The IAEA team reported that they observed remnants of drones at this and two other impact locations at the site. At one of them, outside a laboratory, they saw blood stains next to a damaged military logistics vehicle, indicating at least one casualty," it added.