Afghan and international forces have launched an operation to rescue 23 South Koreans taken hostage by Taliban insurgents.

The operation came as a South Korean government delegation arrived in the Afghan capital Kabul to secure the release of countrymen who were seized in the Qarabagh district of Ghazni province.

In a statement, the Afghan Ministry of Defence said: "Afghan forces and international troops have launched a joint operation for the freedom of the Korean hostages.

"The result of the operation will be announced at a later date."

Taliban spokesman Qari Mohammad Yousuf said the group was holding the captives at different locations and any attempt to free them through force would put the Koreans' lives at risk.

He said insurgents would start killing the hostages if South Korea did not agree to withdraw its 200 military engineers and medics from Afghanistan and the Afghan government did not release all Taliban prisoners.

The South Korean government has said it will withdraw its troops at the end of this year as planned.

The South Korean delegation of eight officials included a deputy foreign minister, a special advisor to the president and Foreign Ministry diplomats.

The 23 Koreans belong to the "Saemmul Church" in Bundang, a city on the outskirts of the South Korean capital, Seoul.

Most of them are in their 20s and 30s and include nurses and English teachers. South Korean President Roh Moo-hyun said in a televised speech the Koreans were providing only free medical or educational services with no missionary intentions.