A huge blast at a gunpowder store in central Kabul destroyed several shops and houses early Wednesday, killing at least four people, police said.

Deputy city police chief Zulmay Khan said the explosion was caused by gunpowder in shops selling ammunition for hunting rifles.

The blast threw piles of burning wreckage into the street and windows were shattered for hundreds of meters around.

• More coverage of the struggle for stability is available in FOXNews.com's Afghanistan Center.

Ali Shah Paktiawal, the criminal director of Kabul police, had said earlier it was a car bomb and had killed at least four or five people. But after further investigation, Paktiawal said it "was not a terrorist act."

At least three others were hurt and pulled from the rubble of collapsed mud-brick buildings and put into waiting ambulances. People, including crying relatives, used their hands and shovels to dig through the debris for more feared trapped inside.

Khali Abdul Wahid, a leader in the area, said there were 400 shops near the blast site, and at least 100 were destroyed or damaged.

A reporter on the scene said at least 20 shops were completely destroyed.

Most of the shops were shut at the time of the blast around 6:30 a.m. in part of the city where many buildings are already ruined from years of conflict.

Khan said most of the casualties were caused by houses collapsing in the explosion.

Mahmadullah, 22, had been opening his shop when the explosion caused it to collapse on him. Rescuers pulled him out alive from the rubble.

His father, Mohammad Ashim, had a cut on his nose and on his head, and stood barefoot outside on the rubble. He said his other son also was injured.

Visit FOXNews.com's Afghanistan Center for complete coverage.