New classified intelligence obtained before the May 29 disappearance of the journalist, Saleem Shahzad, 40, from the capital, Islamabad, and after the discovery of his mortally wounded body, showed that senior officials of the spy agency, the Directorate for Inter-Services Intelligence, directed the attack on him in an effort to silence criticism, ''New York Times'' reported quoting two senior Obama Administration officials.
The intelligence, administration officials said they believed was reliable and conclusive, showed that the actions of the ISI, as it is known, were "barbaric and unacceptable".
But the disclosure of the information could further aggravate the badly fractured relationship between the US and Pakistan, which worsened significantly with the American commando raid two months ago that killed Osama bin Laden in a Pakistan safehouse.
The newspaper said Obama administration officials will deliberate in the coming days how to present the information about Shahzad to the Pakistani government, an official said.
The disclosure of the intelligence was made in answer to questions about the possibility of its existence, and was reluctantly confirmed by the two officials.
"There is a lot of high-level concern about the murder; no one is too busy not to look at this," said one.