UPDATE 3 - Blasts at Ammunition Depot Rock Bulgarian Capital Sofia, Airport Closed

In another statement the Ministry said the name of the village where the blasts occurred was Chelopechene, not Chelopech as it stated earlier. The depot, located near Chelopechene some 10 kilometres north of Sofia, was housing artillery shells due to be decomissioned, Army Chief of Staff Gen. Zlatan Stoikov told state-run radio broadcaster BNR.

"There is no danger of air pollution by warfare gases," the Defence Ministry added. It also said no rise in radiation levels was detected at the site.

"We take measures to evacuate the people around, as the blasts can continue," Stoikov said.

"No people were injured", Defence Minister Nikolay Tsonev said. It was not immediately clear what caused the blasts which woke thousands of residents shortly after 6:30 a.m. (0330 GMT).

"The most likely reason for the explosion in Chelopechene is human error," Sofia municipality's security expert Ivan Boyadzhiev said in a interview for local news agency Focus.

"I'm sure that there was no intention of causing the explosion and that the accident was not caused by meteorological conditions," Boyadzhiev added.

Currently there are still single blasts at intervals of five to six minutes, Tsonev said. Only when there has been no explosion for an hour will it be safe for an investigation team to enter the depot, he added. The minister told reporters that aerial photos show the whole depot in ruins with no more major explosions expected.

About 1,7000 people from some 600 houses in a six-kilometres zone around the depot were evacuated and if they cannot return to their homes for the night, the ministry will provide shelter, food and water, Emergency Situations Minister Emel Etem said.

Sofia airport, located some five kilometres from the blast site, was closed to all flights from 0715 local time but the Transport Ministry said it will reopen at 1730. All flights were redirected to Plovdiv, 130 kilometres southeast of Sofia.

The Transport Ministry reported shattered windows at a number of airport buildings.

The warehouses also stored around 20 tonnes of TNT explosive which could damage an area of up to eight kilometres in diameter, Darik radio quoted Interior Ministry Chief Secretary Pavlin Dimitrov as saying but according to the latest reports the TNT burned out without exploding.