The Afghan Foreign Ministry is denying claims by Taleban militants that they have killed two German hostages. Earlier Saturday, a Taleban spokesman said the hostages were killed when a deadline passed for the German and Afghan governments to meet Taleban demands. The insurgents are demanding the release of all Taleban held in Afghan prisons and an end to Germany's military presence in the country. From Islamabad, Benjamin Sand reports Afghan officials say it looks like one of the hostages may have died, but from a heart attack, the other is still alive.

A purported Taleban spokesman told local reporters by phone that both men were shot and killed Saturday afternoon.

The news ricocheted across Kabul's fairly tight knit expatriate community. But within hours fresh reports suggested all had not been lost.

The Afghan Foreign Ministry said it still could still confirm the report.

German officials too said they had no independent verification of the Taleban's claims.

And then Foreign Ministry spokesman Sultan Ahmad Baheen, told reporters Saturday evening that it appeared the Taleban were lying.

He says the latest information they have is only one man died but he died naturally, from a heart attack. The second German is still alive.

Afghan officials insist it is still too soon give up hope.

Earlier Saturday, German Chancellor Angela Merkel rejected the Taleban ultimatum to withdraw Germany's 3,000 troops from Afghanistan. Ms. Merkel said the troops would stay in place.

She is not the only international leader seeking the release of hostages in Afghanistan.

Thursday, Taleban militants kidnapped at least 18 South Koreans.

The evangelical Christians were traveling between Kabul and the southern city of Kandahar, territory considered a Taleban's stronghold.

The mass abduction is the largest single group of foreign hostages taken since U.S. led international forces ousted the Taleban regime in 2001.

The militants are threatening to kill all the Korean hostages unless South Korea agrees to withdraw its forces from Afghanistan.

Seoul currently has around 200 non-combat forces in the country and already has plans to redeploy them by the end of the year.

South Korean president Roh Moo-hyun issued a televised appeal for the hostages' safe return on Friday and insisted Seoul would conduct "sincere" negotiations for their release.

A high power delegations is scheduled to fly from Seoul to Afghanistan Sunday to meet with Afghan President Hamid Karzai to discuss efforts to free the South Korean Christians.

Afghan officials say kidnapping cases in general are on the rise as Taleban militants seek new ways to undermine support for Afghanistan's U.S.-backed central government.