SEOUL -- Six leaders from South Korea's biggest Buddhist order have quit after secret video footage showed some supposedly serene monks raising hell, playing high-stakes poker, drinking and smoking. 

The scandal erupted just days before Koreans observe a national holiday to celebrate the birth of Buddha, the holiest day of the religion's calendar. 

The head of the Jogye order (external link to Jogye Order of Korean Buddhism's site), which has some 10 million followers, or about a fifth of the country's population, made a public apology on Friday, vowing "self-repentance." 

South Korean TV networks aired shots of eight monks playing poker, some smoking and drinking, after gathering at a luxury lakeside hotel in late April for a fellow monk's memorial service. 

"The stakes for 13 hours of gambling were more than 1 billion won ($875,300)," Seongho, a senior monk who uses one name, told Reuters on Friday. 

He said he had reported the incident to prosecutors. 

'They abused money'
Gambling outside of licensed casinos and horse racing tracks is illegal in South Korea and frowned upon by religious leaders. 

"Basically, Buddhist rules say don't steal. Look at what they did, they abused money from Buddhists for gambling," Seongho said. 

The behavior of the supposedly abstemious monks has led to Korean media speculation of a power split within the order. 

While members of the order's head office offered to resign en masse on Thursday amid the controversy, the organization said it would investigate who installed the hidden camera at the hotel, saying it also violates the law, The Korea Herald reported.

The newspaper reported that "insiders" said there has been a political dispute among top monks and the secret filming was probably done to help eliminate members of the order.

 Seongho said he had obtained a thumb drive that contains a video clip from a camera hidden in the hotel. He would not say who his source was because of recent threats made against him. 

The wayward monks appear to have upset many in Korea. 

"A group of monks who gamble, drink and smoke in a hotel room is tainted in the eyes of all people in the nation," civic group Buddhist Solidarity for Reform said in a statement. 

The scandal also excited attention on Twitter, with some posts calling for reforms within the sect. 

"It can be good news. Please, Jogye Order, cut out the rotten part before it gets worse and take this opportunity to be reborn," one Twitter post said. 

Reuters contributed to this report.

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KATMANDU, Nepal -- Police in Nepal have arrested a U.S. man who was allegedly a member of a smuggling ring that sent illegal drugs into the United States by concealing them in Buddhist prayer wheels.

The drugs, which were also put into metal bowls, were sent via Federal Express, authorities said.

Police official Navraj Silwal said Kristian Peter Stiegler, 45, was detained while trying to send 2.5 pounds of hashish, a form of cannabis, and 2 pounds of suspected opium.

If tests confirm the substance is opium, Stiegler could face up to 20 years in prison.

However, Silwal said Stiegler would likely get a lighter sentence because he was cooperating in the investigation into the alleged drug ring.

'Hefty sum'
Silwal said Stiegler has lived in Nepal and India for three years and was suspected of sending several drug shipments.

The Himalayan News Service said hashish was allegedly sent to Europe, as well as to the United States.

It reported the smuggling ring was discovered when police in Dubai intercepted two parcels of hashish that Steigler had allegedly sent to a New Orleans woman.

"Stiegler used to send hashish to the woman via airmail in the form of parcels and the woman used to distribute the drug in black market for a hefty sum," Yadav Raj Adhikari, chief of the Narcotic Drug Control Law Enforcement Unit, told the Himalayan News Service.

The Associated Press contributed to this report.