A suicide bomber rammed his car Saturday into an Afghan army vehicle guarding a Kabul compound where Afghanistan's political and tribal elites are to gather next week to debate a security pact with the United States.
The Taliban have claimed responsibility, the BBC reported.
An Interior Ministry spokesman, Sediq Sediqqi, told Reuters there were at least six dead and 22 wounded, both soldiers and civilians, but other reports had 10 dead.
Saturday's attack took place just hours after President Hamid Karzai called on the Taliban to take part in the loya jirga assembly that convenes on Thursday to decide whether to allow some U.S. troops to stay in the country after 2014.
The blast occurred shortly after 3 p.m., fewer than 100 meters from a huge tent where more than 2,000 prominent Afghans are due to gather, a witness told Reuters.
The New York Times reported the target was near the gates of Kabul Educational University. As the area is cleared, more bodies are likely to be uncovered. 
“Students and schoolgirls were passing,” Dr. Ghulam Sarwar Zohair, an employee of a nongovernmental organization with offices nearby, told the Times. “Lots of people got injured and probably killed.” 
“We believe it was meant to bring disorder before we convene the jirga,” said a spokesman for the loya jirga, Abdul Khaliq Hussain Pashayee. “We are hopeful and expect Afghan security forces to provide a better security environment for the representatives of the people who will be meeting next week.” 
The Taliban have been vehement in their opposition to the security pact, calling the loya jirga a “farce.” The force released a statement last week denouncing the security deal and urging Afghans to boycott the jirga. 
The Karzai government, the Taliban wrote, wants to do the Americans’ bidding and “implement a treacherous deal which in our history will forever be known as national sedition and a criminal act against our nation. Under this treacherous deal, undertaken between a master and slave, the barbarian American Army will continue its occupation of our beloved homeland.”