Prime Minister Prayut Chan-o-cha is sending a strong message to people planning to dress "indecently" during the Songkran festival next week.
As the Thai traditional new year approaches, the prime minister used his weekly broadcast on Friday to remind revellers about the strong position of the government against misbehaviour.
"Please be more careful in celebrating this event and refrain from harassing others or dressing indecently in public places," he said in his Returning Happiness to All Thais address on Friday.
"There are laws governing indecent exposure, which will be enforced," he added.
It was his second warning on the issue and came four days after the first message was delivered after a cabinet meeting on Tuesday.
Police in Bangkok have taken the premier's message to heart. Pol Maj Gen Adul Narongsak, deputy chief of the Metropolitan Police Bureau (MPB), said all divisions would set up a special operations centre to monitor the way revellers are dressed at party sites and in clips on social media. Police will take quick action to end any activities deemed to damage public morals or the country's image, he added.
Songkran officially runs from April 13-15 as part of a five-day weekend that ends on April 17.
Recent Songkran festivals have featured an increase in boisterous celebrations involving soaking-wet, scantily clad women. However, the behaviour of men at Songkran is more of a worry.
Just over half of the women responding to a recent survey said they had been sexually harassed at Songkran, a time of year when many male celebrants seem to believe they have a licence to grope.
Gen Prayut on Friday offered people some advice, saying: "You can also dress in traditional costumes."
Unlike other Songkran celebrations in the past, the event this year takes place as the country is facing its worst drought in two decades.
The latest update on the Disaster Prevention and Mitigation Department on Friday shows 27 provinces have been declared disaster areas due to severe drought, with 10 having insufficient water supplies for consumption.
Authorities have been trying to discourage large-scale use of water given the current conditions. "Traditional" Songkran practices involving large water tanks on pickup trucks are being frowned on.
The prime minister said he also hoped revellers would be careful about splashing water.
"I would like to urge all Songkran revellers to use water sparingly while engaging in a Thai tradition that has been around for generations," he said.