KANDAHAR, Afghanistan – A bomb exploded Saturday outside the provincial governor’s office in the Afghan city of Kandahar, killing one policeman and wounding at least 14 civilians, officials said.

The attack reflects deteriorating security in the largest city in the country’s volatile south, where NATO is preparing for a major operation seen as key to combating the insurgency. Gov. Tooryalai Wesa was not in his office at the time.

The bombing also comes a day after a national peace conference in Kabul boosted President Hamid Karzai’s plans to seek negotiations with the Taliban in a bid to end the nearly nine-year war.

Kandahar police Chief Sardar Mohammad Zazai said the explosives were strapped to a bicycle on the street outside the compound where the governor lives and works.

The governor’s spokesman, Zulmai Ayubi, said the 14 wounded included five children. Among the wounded, four were in critical condition, he said.

“The explosion happened in front of us,” witness Suliman Shah said. “I heard it and also saw one person get blown backward, out of the back of his vehicle.”

Taliban militants are the most likely suspects. The hard-line Islamist movement, ousted from power in 2001 but now a formidable militant force, says it will keep fighting. Its leaders say no talks are possible until foreign troops withdraw from the country — a step Karzai cannot afford with the insurgency raging. U.S. officials contend the Taliban leadership feels it has little reason to negotiate because it believes it is winning the war.

Karzai, who organized the conference that ended Friday, clearly got what he wanted from it: a mandate for his peace efforts and his government months after winning an election tainted by fraud. It also represented the first major public debate in Afghanistan on how to end the war amid widespread belief here that the insurgency cannot be defeated militarily.

“The one significance of the jirga is that for the first time a collective and structured voice of Afghans for peace has been presented to the government and to the international community,” said Nader Nadery, deputy chairman of Afghanistan’s Independent Human Rights Commission.

U.S. State Department spokesman P.J. Crowley praised the jirga as providing “a national consensus to pursue a political strategy to reduce the danger posed by the insurgency.”

While active militant leaders were not invited to the jirga in Kabul, some former Taliban and their sympathizers came. Many stay in contact with Taliban foot soldiers — who till their farms by day and lay roadside bombs by night.

Nadery said it’s these rank-and-file Taliban who could be pressed by their communities to embrace the peace process, particularly if backed by government incentives.

The jirga’s resolution calls for militants who join the peace process to be removed from a U.N. blacklist. It also supports the release of Taliban prisoners in U.S. and Afghan custody — and Karzai promised to make that a priority as a goodwill gesture to the militants.

But it says insurgents who want to take part must cut their ties with foreign terrorist groups such as al-Qaida.

In other violence, two British soldiers were killed in a gunbattle with insurgents Friday in southern Helmand province, the U.K. Ministry of Defense announced Saturday.

Also Saturday, dozens of angry residents blocked a highway from western Herat city to the Iran border after a shooting involving NATO forces in which an Afghan civilian died and several others were arrested. Deputy provincial police chief Delawer Shah said NATO forces opened fire after their convoy came under militant attack.