Pakistan\'s Foreign Ministry has summoned a senior US diplomat to protest recent drone strikes targeting militants in the country\'s northwest tribal region near the Afghan border. Pakistani officials told the diplomat, who was not identified, that the attacks were unacceptable, unlawful and a violation of Pakistan\'s sovereignty. Islamabad\'s protest Thursday follows a string of three drone attacks in three days earlier this week in the North Waziristan tribal area. The strikes are very unpopular in Pakistan because many people believe they mostly kill civilians an allegation disputed by the US.