Afghan officials say they have evidence a foreign intelligence agency was involved in Monday's attack on the Indian Embassy in Kabul.
Afghan presidential spokesman, Humayun Hamidzada, did not name the agency, but Tuesday said it was "pretty obvious" who was behind the suicide car bomb attack that killed at least 41 people and wounded more than 150 others.
In the past, Afghan officials have accused Pakistani agents of being behind several attacks on their soil.
Hamidzada told reporters the sophistication of the attack, the kind of materials used, the specific targeting - everything - had the hallmark of a particular intelligence agency that has conducted similar terrorist attacks in Afghanistan in the past.
Speaking in Malaysia, Pakistani Prime Minister Yousuf Raza Gilani Tuesday denied Pakistan's involvement - saying his country is not interested in destabilizing Afghanistan.
No one has claimed responsibility for the bombing that killed four Indian nationals.
A White House spokesman, Gordon Johndroe, called the attack a needless act of violence. Afghan President Hamid Karzai has also condemned the bombing.
The U.N. Security Council joined Secretary-General Ban Ki-moon in strongly condemning the attack.