Pakistani officials say at least 20 people were killed on Saturday in two suicide bombings targeting Pakistan's military in Rawalpindi, outside the capital, Islamabad.
The first bomb struck a bus on the main road between Rawalpindi and Islamabad. Police say the bomber rammed a car filled with explosives into the bus carrying employees of Pakistan's Inter-Services Intelligence Agency.
Army spokesman Wahid Arshad says the second attack occurred when a car bomber detonated explosives after he was stopped for an identity check outside army headquarters in Rawalpindi. Arshad says the bomber was killed, and two people were injured in that blast.
Officials suspect the attacks are linked to military operations against pro-Taliban militants in the country's troubled Northwest.
In other news, government officials battling a militant uprising in the North West Frontier Province say they have imposed a food blockade in the troubled Swat Valley region.
Military checkpoints are stopping all food shipment into the region, where recent clashes have killed more than 220 people.
Unrest erupted in the Swat Valley last month when pro-Taliban cleric Maulana Fazlullah declared a holy war against the government.
Since then, fighters loyal to Fazlullah have seized control of several towns and police stations in northern Pakistan, without encountering much resistance from the army.
President Pervez Musharraf justified his decision to impose emergency rule in the country three weeks ago by saying it was necessary to curb rising extremism in the country.