BALIK PULAU/GEORGETOWN - Penang police are investigating a video showing 18 nudists including Malaysians and Singaporeans taking part in nude events at a beach in Teluk Bahang.

The Star newspaper reported on Wednesday that the five-minute video shows the group in the nude participating in activities such as body painting, a relay race, a group crab-walk and a Gangnam-style dance with one woman riding a man who was on all fours like a horse, among others.

The video was reportedly shot at Teluk Kampi, which is touted as the longest beach at the Penang National Park, said the newspaper.

New Straits Times (NST) quoted the police as saying that seven of the 18 nudists are Malaysians, four are Singaporeans, two from Myanmar and one each from the Philippines and India. The remaining nudists have yet to be identified.

The newspaper quoted state police chief Datuk Abdul Rahim Hanafi as saying the police have taken statements from 10 people and groups, excluding the nudists, over the incident.

"We now know what had taken place but will not reveal anything more until we have completed our investigations," he told reporters on Wednesday .

Police had taken DNA samples and finger prints from a house where the nudists were believed to have stayed in, said NST. A team of 10 personnel from the districts' forensic unit had started combing for evidence at several spots where the nudists were believed to have hung out.

If found guilty under Section 509 of the Penal Code for committing a gesture intended to insult the modesty of a person, they face a jail term of up to five years, a fine or both, said the police.

NST reported that a user, identified only as Albert, had uploaded the video, titled "Penang Nude Sports Games 2014", on video sharing website Vimeo about two months ago. He thanked one Miss Chew for organising the event and the "naturists for coming and making it a history in Malaysia".

The report said an announcement - "See you this coming Dec 5, 2014, the Asian Nude Sport Games and Conference in Penang, Malaysia" - was also found in the video.

The 2-km Teluk Kampi beach is about 4.5km from the entrance of the park and about 35 minutes by boat from the Teluk Bahang jetty.

The Star reported that a Penang National Park patrolman who was on duty when the 'naked sports' took place is under investigation. Park management committee member Datuk Shah Headan Ayoob Hussain said they were still waiting for a report from the man for not informing the management of the indecent acts.

Shah Headan said initial probe found that the patrolman had issued repeated reminders to the nudists that they were not allowed to strip in the beach.

"But they did not heed the patrolman's advice. We are now investigating the patrolman on why (he) did not inform us over the nude event,'' he said.

"He could be threatened or ridiculed by the group over this … that's why he dared not report the incident.

"But we will investigate. As far as we are concerned, he has no authority to take action against the group of people. He can only advise," he said at a press conference at the Penang National Park office on Wednesday.

Penang Chief Minister Lim Guan Eng said the state government was not aware of the purported event.

The state would not even approve a casino, he said, let alone sanction an event for nudists.