US drones attacked Pakistan's volatile North Waziristan province today, killing at least 16 believed militants, BBC News cited Pakistani officials as saying.
The assault comes a day after Pakistan formally complained to a US diplomat over the drone strikes, said Al Jazeera, arguing that they damage the region and often take civilian lives.
The move signals the possibility of a return to a standoff on the controversial issue, with Islamabad having cut off a key NATO supply point in protest over the issue earlier this year.
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Pakistan says such strikes undermine the nation's authority, but the US maintains they are necessary for keeping a growing militant-led insurgency in neighboring Afghanistan at bay.
The US assault today was the fourth and most deadly in a week, according to Al Jazeera.
Pakistan's foreign ministry issued a statement Thursday saying that a “senior US diplomat was called to the Ministry of Foreign Affairs and informed that the drone strikes were unlawful, against international law and a violation of Pakistan’s sovereignty. It was emphatically stated that such attacks were unacceptable,” the Associated Press said, noting the individual was not named.
Pakistani intelligence officials today said US drones fired missiles into three suspected militant holdouts today in the tribal North Waziristan region, according to AP.