KABUL, Afghanistan - A rocket exploded in a field near the U.S. Embassy in Kabul on Thursday about two hours after Defense Secretary Donald H. Rumsfeld met with Afghanistan's leader in another part of the capital.
A U.S. military official said Rumsfeld had safely left the country to continue his tour of Central Asia. No one was injured in the explosion, which one official blamed on fighters from Afghanistan's ousted Taliban rulers or their ally, renegade warlord Gulbuddin Hekmatyar.
It was not immediately known whether Rumsfeld was still in Afghanistan when the blast occurred.
The attack underlined the country's fragile security situation ahead of a key Afghan gathering, or loya jirga, next week to approve a constitution and the national elections slated for June, the first since U.S.-led forces drove the Taliban from power.
In southwest Afghanistan, Taliban fighters ambushed a convoy of 60 government workers preparing for the country's first census in 1979. One census worker was killed and 11 wounded, officials said.
A Taliban spokesman claimed responsibility for the attack. "We will give such treatment to people who work with the Americans, whether they are foreigners or locals," Mullah Abdul Hakim Latifi said in a satellite telephone call to an Associated Press reporter in Kandahar.
After talks with Afghan leader Hamid Karzai in Kabul, Rumsfeld insisted stepped-up Taliban attacks in the south and east would not delay the June vote.
"I can't imagine that there will be any type of a delay from the standpoint of what you suggested," he said at a joint press conference with Karzai. Rumsfeld said that Afghan and coalition forces were capable of managing any situations that arise "quite well."
Karzai said Afghanistan was on a "path to freedom" that the former ruling Islamic hardliners could not stop.
"We, together with the international community, have the responsibility ... to provide the means for the Afghan people to cast their free vote," he said, adding that voter registration had just begun. "The Taliban, terrorists, whoever they are, will not be able to disrupt the process."
On Nov. 22, a rocket exploded in the garden of an upscale hotel in Kabul frequented by foreigners. No casualties occurred, but the Intercontinental, which was damaged by the blast, is located near the area where the loya jirga will begin meeting on Dec. 10.
Rumsfeld's meeting with Karzai took place at the Presidential Palace in Kabul, around two miles from the U.S. Embassy.
About two hours later, the rocket exploded in a military athletic field across the street from the embassy, about 300 yards from the building, witnesses said.
Police and soldiers searching the field with flashlights found a piece of shrapnel that appeared to come from a truck-launched rocket, Kabul military commander Mohammed Ayub Salangi said.
The blast occured about 100 yards from the downtown headquarters of the 5,700-member international peacekeeping force patrolling Kabul, said a spokesman for the force, Maj. Kevin Arata.
Matyullah Ramani, a senior Kabul police officer, blamed the Taliban or Hekmatyar. "They are trying to disrupt the loya jirga," Ramani said.
The loya jirga, a tradition form of national assembly gathering prominent figures from around the country, is to approve a constitution, clearing the way for June's presidential election and parliamentary ballot after that.
Hekmatyar, a former prime minister, heads Hezb-e-Islami, a faction that fought Soviet Russian troops in Afghanistan in 1980s. He is suspected of having urged Afghans to fight the U.S.-led coalition forces now in the country and American forces are searching for him.
While international troops back Karzai in the capital, Afghanistan's government has little control outside Kabul because of attacks by pro-Taliban insurgents and fighting among powerful provincial warlords. Recently, terrorists attacks have increased sharply, forcing U.N. workers and relief agencies to reduce their work in the south and east.
Before traveling to Kabul on Thursday afternoon, Rumsfeld had met in northern Afghanistan with two of its main warlords and said he was satisfied that they have begun disarming, even though that was happening more slowly that he had hoped.
More than 11,500 U.S.-led coalition forces are hunting down followers of the Taliban and its allies, especially along the border with Pakistan, where some of them operate from.
Some 35 Americans have died from hostile fire since the October 2001 start of the Afghan war, according to the U.S. military. The Taliban regime was driven out of Kabul in late 2001.