The 13 dead reportedly include six members of the Wolesi Jirga, the lower house of Afghanistan's parliament.
The lawmakers were members of the Wolesi Jirga's National Economy Commission, a group tasked with monitoring reconstruction efforts in the country.
Afghan Health Minister Sayed Mohammad Amin Fatemi told RFE/RL's Radio Free Afghanistan that the six lawmakers killed in the attack included Sayed Mustafa Kazemi, the head of National Economy Commission of the lower house of parliament. He named the other slain lawmakers as Matin, Nazukmir Sarferaz, Saif u-Rahman, Sebghatullah Zaki, and Haji Sayed Zarif. Three children and four of the legislators' bodyguards were also killed.
Fatemi said that two other lawmakers, Sayed Hashem Fullad and Shukria Isakhaid, were injured. Of the total of 81 injured, the minister said that 42 were children who were present to greet the delegation.
Kazemi had served as minister of commerce in Afghan President Hamid Karzai's transitional administration. After his election to parliament in 2005, Kazemi founded the first opposition parliamentary group in post-Taliban Afghanistan -- Estiqlal-e Milli, or the National Independence Group.
Kazemi also was the spokesman of the United Afghan National Front, a political alliance mostly comprising individuals who had fought together against the Taliban regime as the former United Front, also known as the Northern Alliance.