Emergency crews outside the home of Burhanuddin Rabbani in Kabul. The Taliban has claimed responsibility for the attack on the head of Afghanistan's peace council.
The attack comes just a week after a 20-hour siege on the capital. It is also the highest profile killing since President Karzai's younger half-brother was killed.
There are concerns Rabbani's killing will have a negative long-term impact on diplomatic efforts.
The assassination didn't deter a scheduled meeting between Karzai and president Obama at the United Nations where Obama condemned the attack.
SOUNDBITE: U.S. President Barack Obama saying:
"He was a man who cared deeply about Afghanistan and had been a valued advisor to President Karzai. He made enormous contributions to rebuilding the country so it is a tragic loss and we wanted to extend our heartfelt condolences to you, his family and the people of Afghanistan."
Both leaders vowed to go forward with efforts to find a peaceful end to the war.
Deborah Gembara, Reuters.
