U.S. and Pakistani authorities disagree sharply over claims that senior al Qaeda leader Ilyas Kashmiri was killed in a recent missile strike, officials from both countries said on Monday, suggesting sharp strains persist between authorities in Washington and Islamabad. Two days ago, intelligence officials in Pakistan claimed that Kashmiri, a figure in both al Qaeda and a Pakistan-based affiliate, was killed by a U.S. drone-borne missile in northwestern Pakistan. Pakistani officials subsequently issued a series of statements about Kashmiri's death. The nation's interior minister told reporters on Monday: "I can confirm 100 percent that he is dead. I got this information this morning." But U.S. officials familiar with counterterrorism activities in the region said they still were unable to confirm Kashmiri's death. It was more likely than not, they said Monday evening, that the militant leader was still alive.