SIX senior Buddhist monks offered to resign this week after they were captured on secret video footage drinking, playing poker and smoking at a luxury hotel in South Korea.

The leader of the Jogye Order of Korean Buddhism made a public apology today and said an internal investigation into the footage was launched last week, The Korea Herald reported.

The video - recorded by a hidden surveillance camera in a hotel room in Jangseong - shows the men gambling and carousing before a memorial service for a dead Zen Master at Baekyang Temple on April 23.

A former member of the Jogye Order's head office lodged a complaint and accused eight monks of being involved in 13 hours of gambling. The total sum won during the poker game was one billion won ($875,000).

Among the group were two spiritual leaders, high-ranking monks and abbots from branch temples.

Ven. Jaseung, who leads the Jogye, ordered severe disciplinary actions against those involved.

He also announced an investigation into the installation of the camera, which he said violated the law.

Critics claim the camera was put there by opponents to try and bring down the monks.

Around 12 million Koreans are Buddhists, according to government data.

There are 25 Buddhist orders in South Korea, with the Jogye the largest.