Afghanistan's Interior Ministry says the militant group claiming to have kidnapped three U.N. workers is not, in fact, the group holding the captives.

Interior Ministry spokesman Latfullah Mashal says an unidentified "criminal gang" is the group actually responsible for the abduction of the three U.N. workers in Kabul late last month.

He dismissed weeks of claims by militants calling themselves the Jaish-e Muslimeen, or Muslim Army, that they have the hostages.

The Jaish-e Muslimeen, who have demanded the freeing of imprisoned members of Afghanistan's former Taleban regime, disputed Mr. Mashal, insisting they are the real captors.

Major Scott Nelson, the spokesman for the U.S. forces in Afghanistan, said he did not know where the captives are, despite speculation they are still in Kabul.

"If we knew specifically where they are located at, I think they would be free by now," he said.

The captives - an Irish-British woman, a Filipino man and Kosovar woman - had been assisting the Afghan government in organizing post-war elections when they were taken from their U.N. car at gunpoint.

Following the abduction, the captors released a videotape of the hostages. Mr. Mashal suggested that the criminal gang, and not Jaish-e Muslimeen, recorded that video.

The Afghan government is working with the U.S. military and international peacekeepers based in Kabul to secure the hostages' release.

A spokesman for the peacekeepers, Lieutenant Commander Ken MacKillop, says he sees the continuing of negotiations to free the captives as a positive sign.

"The fact that indicators suggest that these three individuals are still alive, I think that is testament to the success the government and the hostage negotiators have had over the past couple of weeks."

The abductions have sparked an outcry among some portions of the Afghan public, given the general popularity enjoyed by the United Nations throughout much of the country.

Some Afghan citizens have even offered themselves as hostages in place of the three captives.