A female election worker was killed by a mine blast Thursday in eastern Afghanistan (search), officials said, while six Afghan soldiers died in an attack in the west blamed on the Taliban (search).

The mine hit a pickup truck on a road in Khogyani district of Nangarhar province, 60 miles east of the capital, Kabul, said Faizan Ul-Haq, a spokesman for the provincial government.

Manoel de Almeida e Silva, a spokesman for the United Nations (search), which is co-organizing the elections, said the driver was seriously hurt and had been flown to Kabul for treatment.

Three other passengers, two men and another woman, suffered only light injuries and were able to return to their homes, Almeida e Silva said.

Nobody claimed responsibility and officials said it was unclear if the mine was freshly laid or a leftover from Afghanistan's recent wars.

A string of deadly assaults have hit election workers and Afghans signed up to vote in the first polls since the fall of the Taliban in late 2001.

On June 26, three female election workers were fatally wounded when a bomb hit their vehicle in Jalalabad, the capital of Nangarhar. Taliban supporters claimed responsibility.

The day before, as many as 17 Afghan men were executed by suspected Taliban guerrillas in Uruzgan province, apparently because they were carrying voter ID cards.

More than 6 million Afghan have registered to vote, despite the threat of violence. Afghan officials are still wrangling over a date for the election, which is expected to be held sometime in October.

Gunmen opened fire on the soldiers as their patrol vehicle was rolling along a section of the national ring road in the western province of Farah, provincial government spokesman Abdul Mohammed said. Four soldiers also were wounded in the attack.

Mohammed said: "The Taliban did this" but didn't elaborate.

Taliban militants have killed scores of Afghan security forces this year as part of a bloody campaign to prevent President Hamid Karzai's (search) government from stabilizing the country.

Still, U.N. officials say some violence in Farah and other provinces has been over drug-smuggling.

Afghan militias and police are widely suspected of involvement in trafficking opium and heroin.