In the latest incident Thursday, rocket attack carried out by Taliban insurgents in Yaqubi district of Khost province in east Afghanistan killed one civilian and injured two children, a local official said.

"The rocket fired by rebels hit a residential house in Yaqubi district this morning killing one civilian and wounding two others both children," head of health department in the province Amir Badshah Mangal told Xinhua.

Earlier in the day, police in Kabul killed two suspected suicide bombers in eight district, a police officer said.

Afghan President Hamid Karzai holds up his inked stained finger after voting in the presidential election in Kabul August 20, 2009. [Xinhua]

"Three suicide bombers took position in a building and attempted to target police station in 8th precinct but police shot them dead before going to action killing two of them," a police officer at the site of the incident told Xinhua but he refused to be identified.

Meantime, Taliban purported spokesman Zabihullah Mujahid in talks with media via telephone from an undisclosed location claimed responsibility, adding the militants were fighting with police.

Taliban fighters who have vowed to derail the voting process have carried out several rockets and bomb attacks in parts of the country including their birthplace Kandahar.

Rocket attacks earlier killed four security personnel in Ghormach district of northwest Faryab province Thursday morning while four rockets attacked Kandahar but caused no loss of life.

Moreover, skirmishes and militants activities claimed the life of police district chief in northern Baghlan province while two insurgents have been killed in Imam Sahib district of Kunduz province.

Afghans line to cast their ballots at a polling station in Kabul, capital of Afghanistan, on Aug. 20, 2009. The people of Afghanistan begun voting Thursday morning amid tight security to elect the country' s president and 420 members of the provincial councils. [Zabi Tamanna/Xinhua]

Among the remaining 32 presidential candidates, incumbent President Hamid Karzai is leading in popularity and favor.

A latest poll showed that Karzai enjoyed 44 percent votes while his main rival Dr. Abdullah Abdullah, former Foreign Minister with Karzai government, got 26 percent.

The Afghan Election Commission said initial result of presidential election would be announced 48 hours after the vote ends while preliminary result would be announced on Sept. 3 and official result will be finalized on Sept. 17.

The election is a test for US government's new strategy for Afghanistan. US President Barack Obama has deployed 30,000 extra troops in Afghanistan this year, increasing the total number of foreign troops to 100,000, including 63,000 Americans.

The US military said Wednesday six US soldiers were killed in separate incidents, raising American troops' death toll to 32 this month.