Mike Mullen: Pakistan sanctioned killing of journalist Saleem Shahzad

Admiral Mike Mullen, the highest ranking officer in the U.S. military, said Thursday that Pakistan "sanctioned" the killing of respected Pakistani journalist Saleem Shahzad.

Shahzad, known for his coverage of the infiltration of Islamic militants into Pakistan's security agencies, was kidnapped from near his Islamabad home in May and found dead two days later with torture marks on his body.

"It was sanctioned by the government," Mullen told journalists during a Pentagon briefing in Washington, as reported by BBC. "I have not seen anything that would disabuse that report that the government knew about this."

(More from GlobalPost: Pakistan journalism Saleem Shahzad found dead after disappearing Sunday)

Mullen is the first Amercian official to publically accuse Pakistan of involvement in the kidnapping and murder of Shahzad, the New York Times reports.

Mullen's comments about the death of Shahzad are likely to worsen ties between Pakistan and the United States, it states. The relationship between the two allies has been particularly tense since U.S. forces raided a compound in Abbottabad, Pakistan, and killed Al Qaeda leader Osama bin Laden May 2.

The admiral did not say whether Pakistan's powerful syp agency, the Inter-Services Intelligence (ISI), was invovled in the murder. Many in Pakistan have accused the ISI of the death, but it has denied any involvement.

A Pakistani government spokesman called Mullen's remark "extremely irresponsible," Reuters reports.

"If it is true, than the statement is extremely irresponsible,” a Pakistani government spokesman said, according to the AFP news agency. “It will not help in investigating the issue.”

The Pakistani government has said it set up a judicial commission to investigate Shahzad’s death.