The remaining 22 South Koreans kidnapped by the Taliban in Afghanistan are alive, the Afghan deputy interior minister said on Friday, hours after the passing of the latest deadline set by the group.

|PIC1|"They are alive and fine," Munir Mangal, who also heads an Afghan team trying to secure the freedom of the Christian hostages, told reporters in Ghazni.

He said an Afghan delegation was holding talks with the Taliban and had appealed to the group to not issue further deadlines as the government was keen to resolve the crisis "peacefully".

He did not say if the Taliban had accepted the delegation's appeal.

Earlier, a provincial official in Ghazni where the captives are believed to be held, said the Taliban had again extended the mid Friday Afghan time deadline to allow face-to-face talks with the delegation.

The Taliban could not be reached for comment about the fate of the captives and about the reported talks and extension of the ultimatum.

Accusing the government of "killing time and playing tricks", a Taliban spokesman had said earlier they would kill the captives if rebel prisoners were not released by the Afghan government by Friday noon.

The Taliban killed the leader of the 23 volunteers they snatched from a bus on the main highway in Ghazni which lies to the southwest of the capital Kabul last week. Several previous deadlines have passed without them carrying out their threats.

The Taliban spokesman said Afghan authorities had asked for more time after the insurgents presented the government with a list of eight prisoners it wanted released.

"The administration of Kabul has asked us to give them till 12 noon today," spokesman Qari Mohammad Yousuf told Reuters by telephone from an undisclosed location.

"We are waiting for them. We have given them a list of eight prisoners and if they are not released we won't have any other option than to start killing the hostages."

South Korean chief presidential national security adviser, Baek Jong-chun, is expected to arrive in Afghanistan later on Friday to step up efforts to free the hostages.

Afghan President Hamid Karzai has pledged not to swap prisoners for hostages after being criticised 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.

One German and four Afghans snatched separately are also still being held hostage by the Taliban.

The past 18 months has seen rising violence in Afghanistan, with daily clashes between Taliban insurgents and Afghan and foreign troops.