The fate of 22 South Korean Christian volunteers kidnapped by the Taliban in Afghanistan hung in the balance, a day after the group's leader was killed.
The Taliban said the Afghan government had been given until late last night (0630 AEST Thursday) to agree to exchange the group for eight imprisoned rebels, but the deadline passed without word from the kidnappers or government.
Earlier reports by some media that eight hostages had been released were denied by officials, negotiators and a spokesman for the Taliban.
"Yes, they have killed one of the hostages and efforts are under way to have the others released," said Khowja Seddiqi, district chief of Qarabagh in Ghazni province where the crisis has unfolded.
South Korea's Foreign Ministry identified the victim as Bae Hyung-kyu, a founding member of the Saemmul Church south of Seoul, which sent the volunteers to Afghanistan.
Mr Bae, who was killed on his 42nd birthday, co-founded the church in 1998 and has a young daughter.
He had done volunteer work in Bangladesh in April and planned to visit Africa to help the poor after the Afghanistan mission.
The South Korean government said Baek Jong-chun, chief presidential secretary for foreign and security policy, would leave later today for Afghanistan as a special presidential envoy.
"The government and the people of South Korea condemn the kidnapping of innocent civilians and the atrocity of harming a human life," said Baek Jong-chun, presidential Blue House chief national security adviser.
The Taliban accused the government and South Korean negotiators of failing to act in good faith after Kabul rejected the demand for eight named rebels to be freed from prison.
Initially, the Taliban had also insisted that South Korea withdraw all its troops serving with an international force in Afghanistan – something Seoul had planned to do before the end of the year anyway.
"Since Kabul's administration did not listen to our demand and did not free our prisoners, the Taliban shot dead a male Korean hostage," Qari Mohammad Yousuf told Reuters.
Yousuf said one hostage had been killed in a desert area close to where the 23 Koreans — 18 women and five men — were abducted on the main road south from Kabul last week.
'No swap of prisoners'
Afghan President Hamid Karzai has pledged not to swap prisoners for hostages after being criticised at home and abroad for releasing five Taliban from jail in March in exchange for an Italian reporter.
The president and ministers have remained silent throughout the latest hostage ordeal, but Seoul said it would soon dispatch a special envoy to step up coordination with Kabul.
The kidnappings have made travel outside major cities risky for the thousands of foreign aid workers and UN staff in Afghanistan and may weaken support for military involvement among the more than 30 nations with troops in the country.
The past 18 months has seen rising violence in Afghanistan, with daily clashes between Taliban insurgents and Afghan and foreign troops.
Suicide and roadside bomb attacks have spread to areas previously considered safe.
Anxious family members of the Korean hostages have gathered at the offices of a non-governmental agency in Seoul to follow developments on television.
Sounds of crying emerged yesterday when the news came out that one of the hostages had been killed.
About 1,000 people went to the church that sent the volunteers to Afghanistan to pray for their safe return, the broadcaster YTN reported.