As shock and grief pervaded nationwide, Cheong Wa Dae released a statement live on television in the morning, harshly denouncing the Taliban's killing of Bae Hyung-kyu, 42.

"The Korean government clearly states that the organisation responsible for the abduction will be held accountable for taking the life of a Korean citizen. The killing of an innocent citizen cannot be justified under any circumstance or for any reason, and any such inhumane act can not be tolerated," said the statement read out by Chief Presidential Secretary for Security Policy Baek Jong-chun.

Baek was set to fly as the president's special envoy to Kabul to join the crisis team working with the Afghan government for the release of the hostages.

Cheong Wa Dae spokesperson Chun Ho-seon explained that "the gravity of the situation called for the decision to send" Baek to Afghanistan.

Baek said: "The Korean government will exert all possible efforts and cooperate with the governments of Afghanistan and other related countries so that the Korean citizens held hostage will be able to return to the arms of their families safely and at the earliest possible time."

Tension remained high as the militants were still reportedly holding all remaining 22 hostages.

"No one has been released, and there has not been any exchange," Marajudin Pathan, the governor of Ghazni province was quoted as telling the Associated Press over the phone.

"They are still in Taliban custody."

Pathan was also quoted as saying that authorities were in contact with kidnappers early Thursday trying to secure the Koreans' freedom. The militants gave a list of eight Taliban prisoners who they want released in exchange for eight Koreans, he said.