Related readings: Taliban raises demands for 23 Koreans Deadline extended for Korean hostages 23 S.Koreans kidnapped in Afghanistan

Kabul - A purported Taliban spokesman said Wednesday that negotiations for the lives of 23 South Korean hostages have stalled and that the militants planned to kill "a few" of the captives immediately.

Qari Yousef Ahmadi, who claims to speak for the militants, said the Afghan government hadn't responded to any of its demands and the militants would kill "a few" of the hostages by 2:00 pm (0930 GMT).

Though some of Ahmadi's statements turn out to be true, he also has made repeated false claims, calling into question the reliability of his information.

Ali Shah Ahmadzai, the provincial police chief, said he thought talks had been on a positive track and said the new threat was a surprise.

Family members of the kidnapped South Koreans in Afghanistan wait for news about them in Seoul, July 23, 2007. [Reuters]

"I don't know why they've suddenly changed their mind," Ahmadzai said. "My message to the Taliban is to use tolerance and be patient. This (killing hostages) is against the Afghan culture."

The South Korean hostages, including 18 women, were kidnapped last Thursday while riding a bus through Ghazni province on the Kabul-Kandahar highway, Afghanistan's main thoroughfare.

South Korean negotiators have traveled to Ghazni province to take part in the negotiations. Three previous deadlines for the hostages' lives have passed with no consequences.

In South Korea, Foreign Minister Song Min-soon told the legislature that a "safe release may not be necessarily matched by a quick release." He said the hostages were being held in different locations and had no health problems, though South Korea was pushing to send them medical supplies. He gave no further details.