At least six suspected terrorists were reportedly killed and two injured in a drone attack in South Waziristan on Sunday. Those killed are said to have been members of the Mullah Nazir group and the drones struck when they had gathered to offer prayers for another terrorist who had been killed in a drone attack on Saturday.

Despite being a key irritant in U.S.-Pakistan relations, the drone attacks have intensified over the past fortnight at a time when the bilateral relationship is being tested to its core. Of the 20 drone attacks this year, seven have taken place over the past two weeks, according to the Long War Journal which keeps a log on the visits of the unmanned Predators – operated by the CIA — to the tribal areas of Pakistan along its border with Afghanistan.

Though Pakistan had protested the attacks when they resumed last month, the last few have not drawn any criticism from the Foreign Office which has always said they are counter-productive and a violation of the sovereignty.