People who post online and share video clips and photos of indecently dressed women and transgenders celebrating the Songkran festival will face tough punishments, police warn.

People in the photos will also face charges of committing obscene acts in public.

The warnings were given on Wednesday by deputy Technology Crime Suppression Division (TCSD) chief Siriwat Dipho as authorities prepare to strictly enforce laws to ensure safety and order during the Thai traditional New Year this weekend.

Under Section 14 of the Computer Crime Act, people who post lurid images and share them will be subject to a maximum of five years in jail, a fine of up to 100,000 baht or both.

The anti-technology crime police can "locate wrongdoers and take them to justice wherever they are", Pol Col Siriwat stressed.

Once arrested, they cannot claim the acts were unintentional or were not aware of laws in order to escape the penalties.

Indecent video clips and photos have been seen on the internet more often in recent Songkran festivals but they are unacceptable in the Thai cultural context, Pol Col Siriwat said.

"We don't want any person to imitate these acts. We must keep a good Songkran tradition," he said.

The TCSD is currently intensifying its surveillance of online offences, which may increase during the long holidays from April 12 to 16.

Officers in other police agencies are also ready to enforce laws to curb impaired driving and other traffic violations, which are a major cause of high casualties during the festival.

Authorities will not be lenient to wrongdoers who will "receive high penalties", said Interior Minister Anupong Paojinda, who also chairs the Road Safety Centre.

Police will be deployed to set up checkpoints on roads prone to accidents.

According to the Interior Ministry, there are 29 districts across country, marked as "red", meaning they are at high risk of unwanted incidents.

This year, the government is still running the "Seven Dangerous Days" campaign, which will last from April 11 to 17. Officers are told to be alert for deadly traffic violations during the period. Deputy Interior Minister Sutee Markboon said he wants to change the period into the "Seven Safe Days", but this will occur only if all parties give full cooperation.