Rescuers found three charred bodies in the army depot and the body of a woman in a nearby house on Sunday.
US soldiers were helping in the rescue effort while Danish and Norwegian troops were also expected.
Sali Berisha, the prime minister, said the explosions in the village of Gerdec, about 10km north of Tirana, were an accidental blasts triggered during work to destroy excess ammunition stockpiled during Albania's Communist past.
The chain of explosions started on Saturday and continued until early Sunday, severely hampering rescue efforts.
Berisha said the blast destroyed more than 300 houses in the neighbouring village, while a further 2,000 homes and businesses were damaged.
Footage showed a ball of fire shooting up from the site, with shrapnel and shell fragments raining down on homes and cars.
Gerdec was declared an emergency zone, and Berisha promised relief for villagers who lost their homes.
"As soon as the damage is fully assessed, the government will commit all its resources to quickly react and rebuild the totally destroyed zone," he said.
The authorities evacuated 4,000 people from three villages and the surrounding area, with houses two kilometres away damaged by the blasts which lasted for about 14 hours.
On Sunday, army engineers prepared to go into the heart of the base.
Fatmir Mediu, the defence minister, said villagers might have to stay away from their homes for several days.
"We have isolated the area but our fear is that the ammunition could be reactivated because we don't know how much has exploded," he said.
"The other fear is that the ground is so hot that something could be suddenly reactivated. So that's why all the villages around have been evacuated so we can see clearly in the next few hours and days what exactly the situation there is."
The authorities said most of the ammunition at Gerdec was Russian and Chinese artillery shells made in the 1960s, when Albania was under Communist rule.
Berisha said he could not rule out human error, but said the ammunition could have exploded spontaneously because of its age.
Most of those injured on Saturday suffered burns and psychological shock, but at least two were in a serious condition.
Five people, including two girls with severe burns and injuries, were sent to neighbouring Greece for treatment.
A three-year-old was in intensive care. Hospital officials said she was caught by the blast while playing outside a few hundred metres from the explosion.
Two blast victims, a man and a child in a serious condition, were evacuated early on Sunday by the Italian Air Force. Nine other injured are at Tirana airport waiting to be taken to Italy.
Neighboring Kosovo, Greece and Macedonia have sent blood.
In Gerdec, several homes stood only as skeletons, the bricks around their concrete pillars shattered and the red roof tiles blown away across the hillside. The shockwaves uprooted shrubs and cut olive trees to stumps.