Penang police are investigating a video showing 18 nudists, including Malaysians and four people from Singapore, taking part in nude events at a beach in Teluk Kampi, Penang National Park.
In Singapore, people have also been caught for being naked in public.
In an interview in 2010, Adam Road Medical Centre consultant psychiatrist Ken Ung said exhibitionists get a sexual thrill from the look of shock and horror on their victims' faces. Or, he added, they can be exposing themselves just to attract attention.
Those found guilty of appearing nude in public, or in a private location, but visible to those outside, face a fine of up to $2,000 and up to three months in jail.
Here are some cases of public nudity in Singapore:
Man strips naked on MRT train
A 32-year-old man was arrested for taking off his clothes in front of passengers in a rush-hour train on March 15, 2014.
A female SMRT officer approached the man, but he ignored her request to get dressed. Two male staff then arrived to put the man’s belongings on him and drag him out of the train.
Naked man causes stir at Universal Studios theme park
Visitors at the Universal Studios Singapore got a shock when they saw a naked man posing for photos at the entrance of the theme park on Nov 14, 2012.
He was there for about 10 minutes, before the theme park’s security personnel were called in. The man was arrested and was said by police to be of unsound mind.
Woman arrested for boarding bus in the buff
A Chinese woman in her 50s was arrested after boarding a bus naked on Dec 17, 2010.
According to Lianhe Wanbao, she turned up at a bus stop in Ubi Avenue wearing a black blouse and pair of black pants, but slowly stripped, putting her clothes into a large handbag she was carrying.
Naked man orders breakfast at McDonald's
A man walked in stark naked and tried to order breakfast at the Ridout Tea Garden McDonald’s outlet along Queensway at about 4am on Dec 12, 2010.
He was arrested and referred to the Institute of Mental Health for psychiatric assessment.
Holland Village's naked couple charged
Couple Eng Kai Er and Jan Philip were seen sauntering leisurely through a bustling Holland Village in the nude on Jan 24, 2009.
The couple were arrested nearby, dressed. They were each fined $2,000, the maximum fine for an obscene act.