KABUL, Afghanistan (AP) _ U.S. and Afghan troops detained 22 suspected Taliban fighters during a major search operation after a gunbattle in a southern Afghan mountain range, officials said Saturday.
Also, a renegade warlord was taken into custody weeks after a clash with a powerful rival in the west of the country.
Afghan authorities are struggling to improve security for October elections.
No Afghan or American soldiers were reported injured in fighting which broke out Friday and was continuing Saturday in southern Zabul province.
``This operation was launched to improve security for the people of Zabul province,'' Gov. Khial Mohammed told The Associated Press.
U.S. military spokesman Maj. Scott Nelson confirmed the operations in Zabul and neighboring Ghazni province, and said 22 Taliban suspects had been detained.
``We did have a major operation there,'' he said. It was not clear how many American and Afghan soldiers were taking part.
Further east, suspected Taliban fired on a convoy of trucks bringing supplies to a U.S. military base in Khost province, killing a driver and injuring his assistant, said Nashin Uddin, an aide to the local Afghan National Army commander.
The attack occurred on Friday as the convoy made its way to Camp Salerno, a major U.S. base close to the Pakistani border.
Some 18,000 American-led troops are in Afghanistan to hunt down al-Qaida and Taliban fighters, and to help ensure security for landmark presidential elections scheduled for Oct. 9.
The Taliban have vowed to disrupt the elections, and have launched frequent attacks on coalition soldiers, election workers and Afghan voters.
The vote is also threatened by factional violence and the risk of intimidation by regional militia leaders.
The arrested warlord, Amanullah, a Pashtun who goes by only one name, was brought to Kabul on Friday from the western province of Herat, said Jawed Ludin, a spokesman for President Hamid Karzai. Ludin said Amanullah agreed to the transfer, but officials speaking on condition of anonymity said he had little choice and was essentially being kept under arrest.
``He does not have the freedom to go back. He is in custody,'' said a senior Afghan official.
Dozens were killed in fighting which broke out earlier this month between Amanullah's fighters and those of Herat Gov. Ismail Khan, an ethnic Tajik strongman whose autocratic rule has alienated minorities and even some of his own commanders.
Ludin would not comment on speculation that Khan might be removed from power, but said the action against Amanullah was one in a series of steps that will unfold in the coming days.
``What happened to Amanullah was part of a wider plan to take all necessary measures to secure long-term stability in the region,'' Ludin said.
A Western diplomat said Khan was being pressed by the government to accept a senior post in Kabul _ opening the way for the west of the country to be disarmed and cleansed of unpopular faction leaders.
``There is an opportunity to change the equation in that region,'' said the diplomat, who asked not to be identified. ``For him (Khan), the time for something else has come.''
The fighting alarmed Kabul and the United Nations and underscored the need to improve security ahead of the presidential vote. U.N. Secretary-General Kofi Annan has called for an urgent increase in international forces in Afghanistan before polling day.
The men reached a truce only after the U.S. military sent warplanes to the region to make clear that further fighting was not acceptable.
Karzai also sent hundreds of troops from the Afghan National Army to an air base in Herat to help calm the fighting.