ISLAMABAD , Pakistan ( CNN ) -- Pakistan 's foreign ministry said Wednesday that it has lodged a `` strong '' protest with the U.S. ambassador over missile attacks conducted on Pakistani soil by unmanned drones . The aftermath of a suspected U.S. drone attack on a building in North Waziristan . The ministry said it summoned Ambassador Anne Patterson to underscore that such attacks violate Pakistan 's sovereignty and should be stopped immediately . A statement from the ministry said Patterson was also told that the attacks have cost lives and undermined public support for Pakistan 's counter terrorism efforts . The ministry lodged its protests three days after a missile strike from a suspected U.S. drone on a compound in South Waziristan killed 20 people . Pakistan has repeatedly raised objections to foreign nations violating its sovereignty to pursue terrorists . A U.S. ground operation in September that left several civilians dead rankled relations between the two countries . Last week , Pakistan 's parliament passed a resolution that condemned any incursion on Pakistani soil by foreign forces . The resolution called for a review of the country 's national security strategy and said the government needs to safeguard its sovereignty and territorial integrity . The ministry said it handed Patterson a copy of the resolution . The U.S. and NATO , which have troops in Afghanistan , have been seeking a way to effectively battle militants who launch attacks from Pakistan 's swath of tribal areas along the border . They have become frustrated with Islamabad over the years , saying it is not being proactive enough against militants -- a claim Pakistan denies . The United States is the only country operating in the region known to have the capability to launch missiles from drones , which are controlled remotely . In another development , suspected Taliban militants kidnapped three government officials from an administrative office in Pakistan 's tribal region Wednesday , officials said . The militants abducted two employees and a security guard from the Ambar district in Mohmand Agency . Mohmand is in the Federally Administered Tribal Areas , where U.S. and Pakistani officials have reported a presence of militants . Earlier in the day , militants tried unsuccessfully to take control of a school in Mohmand and abduct about 100 students , authorities said . A shootout with Frontier Corps followed , in which one militant was killed and another arrested . The Frontier Corps is a paramilitary force which uses recruits from Pakistan 's tribal areas and is overseen by Pakistani army officers . Also Wednesday , a suicide car bomber detonated explosives outside a police checkpoint in northwest Pakistan , killing two security personnel , officials said . The Wednesday afternoon attack in the Bannu district of the North West Frontier Province also wounded a dozen people , military sources said . The bomber targeted a check point near a military hospital , said the sources who did not want their names revealed because they are not authorized to speak to the media . CNN 's Reza Sayah and journalist Janullah Hashimzada contributed to this report .
U.S. summons Pakistan ambassador over missile attacks . Missile strike from a suspected U.S. drone killed 3 people . Suspected NATO militants kidnap 20 officials from in tribal region .