Chernobyl radiation 'on the rise'

A minute's silence marked the time of the explosion

A Ukrainian scientist monitoring the site of the Chernobyl nuclear disaster has warned that levels of radiation around the destroyed reactor are rising.

Dmytro Hrodzynskyy said the concrete sarcophagus placed over the remains of the damaged reactor was failing.

Radioactive dust is escaping

Professor Dmytro Hrodzynskyy

In an interview published to coincide with the 16th anniversary of the world's worst civil nuclear disaster, the respected scientist said the remaining fuel inside the reactor was heating up.

But other experts said there was no need to worry about further explosions at the site in the Ukraine.

Professor Hrodzynskyy, who heads the Ukrainian Government's commission on radiation security, told the Izvestia newspaper that 24% of babies now born near Chernobyl have birth defects.

Thyroid cancer in local children is now 1,000 times more likely than before the disaster, he said.

Concrete poured over the ruins to seal them is cracking, Professor Hrodzynskyy says

The situation could get worse because increasing levels of radiation have been detected leaking from the site's unreliable casing, he claimed.

"There is more than one kilometre [0.6 mile] of holes and cracks there," he said.

"Fuel is starting to heat up inside the ruined reactor... and radioactive dust is escaping."

The concrete sarcophagus - designed to encase the ruins and hundreds of tonnes of nuclear fuel remaining from the 1986 disaster - was built too hastily and is now failing, the professor said.

Ukraine is dependent on Western financial aid to maintain the sarcophagus and has complained that is does not have enough to do the job properly, a BBC correspondent says.

A spokesman for the International Atomic Energy Agency in Vienna said the agency was aware of the general problems of Chernobyl but could only register official reports filed by national agencies.

There is no chance of a chain reaction inside the reactor

Volodymyr Kholosha, exclusion zone official

The head of the Chernobyl exclusion zone, Volodymyr Kholosha, said there was no reason to talk of new dangers.

"The Ukrainian and foreign experts who permanently monitor the shelter facility see no cause for concern," he said in response to Professor Hrodzynskyy's interview.

"The same has been confirmed by the data received from monitoring equipment."

He denied that fuel was heating up inside the crippled reactor.

He said the sarcophagus had been designed to allow air in and would be replaced as planned in 2007.

"There is no chance of a chain reaction inside the reactor," he said.

About 250 people gathered near the ruins on Friday to observe a minute's silence at 0123 (2223 GMT Thursday), the exact time when Chernobyl's nuclear reactor number four blew up 16 years ago.

Continuing contamination

The explosion spewed clouds of radioactive smoke that spread over much of Europe.

Between 15,000 and 30,000 have since died and the United Nations estimates that nearly six million people continue to live in contaminated areas.

A 30 km (18-mile) exclusion zone around the site is still maintained though there is some talk of trying to generate tourism opportunities in the area.

Chernobyl's other three reactors continued to be used after the accident but the plant was closed down for good in 2000.