The depot, about 12km north of the capital, is used for the destruction of munitions left over from the communist era.

Footage of the incident showed a massive ball of fire shooting up from the site, while shrapnel and shell fragments rained down on homes and vehicles.

A number of homes near the depot were "completely destroyed" in the blasts, according to Juela Mecani, Berisha's spokeswoman.

Hundreds of casualties

Many of the casualties arriving at hospitals for treatment were women and children from surrounding villages. 

Local media reports said most had suffered burns, concussions, broken limbs, or were hurt by flying glass and shrapnel.

In Video

Tirana munitions blasts

Witnesses said that a stream of ambulances and private cars arrived at the military hospital in Tirana carrying the wounded.

One doctor, who compared the flood of people with a toll of war, appealed for residents to donate blood to help the casualties.

The rescue mission, which was initially planned to continue overnight, was suspended until Sunday morning because explosions were continuing at the site.

Neighbouring villages had been evacuated of about 4,000 residents. They have been temporarily housed at the interior ministry and in army facilities in Durres, a town about 40km west of Tirana.

Officials said the blasts damaged the country's international airport, just over one kilometre away, prompting the authorities to suspend flights for 30 minutes.

The blasts were so powerful that they were felt in Tirana and the seaside resort of Durres, about 20km from the base. Reports said that the initial blast was also heard in neighbouring Macedonia, 150km away.

Surplus munitions

A US company is helping Albania to dispose of surplus munitions at the base, but Berisha said there were no foreigners at the site at the time of the initial explosion. 

Ammunition could be heard exploding for
hours after the initial blast [AFP]

Destroying the antiquated weapons is one of the conditions Albania must fulfil to become a member of the North Atlantic Treaty Organisation.|

Along with Croatia and Macedonia, Albania hopes to be invited to join Nato at a summit in Bucharest early next month.

"The problem of ammunition in Albania is one of the gravest, and a continuous threat," Berisha said. "There is a colossal, a crazy amount of them since 1945 until now."

Fatmir Mediu, Albania's defence minister, said that about 100,000 tonnes of excess ammunition was being stored at army depots across the country.

Majlindu Bregu, a spokeswoman for the Albanian government, told Al Jazeera that it was unclear whether the first explosion had been caused by human error or a problem with the equipment used to destroy the munitions.