Radiation levels at the site were within “normal limits”, authorities reported, adding that firefighters were working to contain the blaze.

An image published by Ukraine’s state emergency service showed a large column of white smoke billowing into the sky from the area, parts of which are closed off to the public due to high levels of radioactivity.

The site surrounding the Chernobyl nuclear plant has been largely deserted since 1986, when the plant suffered a catastrophic meltdown.

“As of 10am (0700 GMT) on May 8, the approximate area of the fire was about 1,100 hectares (11 square km),” the Chernobyl nature reserve, which manages the site of the 1986 disaster, said.

The fire broke out on Thursday “as a result of a drone crash”, it said.

It did not say the origin of the drone.

Kyiv has repeatedly accused Moscow of recklessly attacking its nuclear sites, including the Chernobyl complex.

A Russian drone last year punctured a hole in one of the radiation shells covering the reactor unit that exploded in the 1986 disaster.

Ukraine’s state emergency service said rescuers were working to prevent the further spread of the fire.

“Due to strong gusts of wind, the fire is rapidly spreading across the territory, covering new sections of the forest,” it said.

“The situation is complicated by dry weather, strong winds and mine danger in certain areas of the territory, which significantly limits the possibility of extinguishing work.”

The exclusion zone suffered wildfires in 2020, which lasted several weeks and caused a spike in background radiation.

Ukraine, only last month, marked 40 years since the disaster.