Hundreds of Afghans gathered Wednesday to protest the killing of former Afghan president and peace negotiator Burhanuddin Rabbani at his home in the capital Kabul.

Police say Mr. Rabbani, who served as president from 1992 to 1996, was killed Tuesday by a Taliban suicide attacker who detonated a bomb hidden in his turban.

At least four other people were killed in the blast and one of President Hamid Karzai's key advisors, Masoom Stanekzai, was wounded.

On Wednesday, crowds of mourners carrying pictures of Mr. Rabbani and banners gathered on a street outside of his house in protest of his killing.

NATO officials blamed two suicide bombers for the attack, saying they were feigning a desire to conduct reconciliation talks. A Taliban spokesman claimed responsibility telling Reuters news agency that they appointed two articulate and well trained fighters to build contacts with Mr. Rabbani.

Mr. Rabbani was an ethnic Tajik and head of the Afghan High Peace Council, a government team aimed at seeking a political settlement with insurgents.

Mr. Karzai condemned the assassination Tuesday saying the former Afghan president sacrificed his life for the sake of Afghanistan and peace. He spoke ahead of a meeting with U.S. President Barack Obama in New York on the sidelines of the annual U.N. General Assembly meeting, but cut short his visit because of the attack.

U.N. Secretary-General Ban Ki-moon condemned Mr. Rabbani's assassination “in the strongest possible terms.” He said the U.N. remains committed to supporting Afghanistan and its people in attaining peace and stability and to working in close cooperation with them.

In other violence, at least 10 policemen were killed in a bomb attack in southern Ghazni province late Tuesday.

Officials say the police chief for Waghaz District was killed in the attack which occurred as police were conducting a search operation for militants in a area building.