Sebghatullah Mojaddedi, who was briefly the country's president in 1992 and is now the head of the upper house of parliament, was lightly wounded in the attack, which left two attackers and two bystanders dead.
Mojaddedi blamed Pakistan's intelligence service for the assassination attempt and called President Pervez Musharraf "a dishonorable person," saying Musharraf ordered the attack.
Musharraf's spokesman, Major General Shaukat Sultan, called Mojaddedi's comments "absolutely absurd and highly irresponsible."
Pakistani Foreign Office spokesperson Tasneem Aslam said her country condemned the attack and also rejected "the baseless allegations" against Pakistan.
The two countries have exchanged accusations against each other on several occasions in recent weeks.
RFE/RL Afghanistan Report
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