An explosion at a house in the southern Pakistani city of Karachi killed at least six people Friday morning, police said.

City police chief Wasim Ahmad said the blast appeared to have been caused by explosives stored in the house, located in the Baldia area of the city, a mostly Pashtun neighborhood that is a suspected hide-out of Taliban militants.

Police were trying to determine exactly how the explosion occurred. Television footage showed police seizing guns, suicide vests and grenades from the site.

Karachi, Pakistan's largest city and commercial hub, has largely been spared the Taliban-linked violence that has struck much of the rest of the country, a fact that analysts believe is driven by the group's tendency to use it as a place to rest and raise money. But the city has been the scene of frequent ethnic, political and sectarian violence.

On Dec. 28, a bombing against a Shiite Muslim religious procession in the city killed 43 people and wounded dozens. Riots broke out after that attack, with people setting fire to the country's largest wholesale market. The blaze burned for more than two days and destroyed thousands of shops in the area.