The blast hit the headquarters of the Crime Investigation Department in Karachi, said police officer Iqbal Mahmood.[break]
An Associated Press photographer at the scene said there was a 10-feet (3 meter) wide crater outside the several-story building, which was destroyed. The size of crater suggested it was a vehicle bomb.
The building was in a high security part of the city, not far from the heavily fortified U.S. consulate, two luxury hotels and government buildings, including the governor and the chief minister´s residences.
TV footage showed bloodied victims leaving the scene and security officers searching through the debris of the police building.
Dr. Seemi Jamai said five bodies had been brought to a nearby hospital, along with 40 injured.
Pakistan is battling Islamist militants with links to al-Qaida that are trying to overthrow the U.S.-allied government.
The insurgents have repeatedly bombed government, police and Western targets over the last three years.
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