Pakistan has denounced

as "extremely irresponsible" comments by the top-ranking U.S.

military officer that elements of the Pakistan government had

sanctioned the killing of a Pakistani journalist in May.

The remarks by Admiral Mike Mullen are likely to place new

strains on Pakistan-US ties, already seriously damaged

following the killing of Osama bin Laden by US forces in

Pakistan in May.

The death of journalist Syed Saleem Shahzad prompted intense

speculation about the possible involvement of the Pakistan

military's powerful spy agency, Inter Services Intelligence

(ISI), but Mullen said on Thursday he could not confirm

involvement of the ISI. Reuters