Deputy national police spokesman Pol Colonel Krissana Pattanacharoen said on Thursday they were seeking an Interpol Blue Notice, which asks member countries to locate, identify or obtain information on a person of interest in a criminal investigation.
Once Vorayuth’s location is known, the Office of the Attorney-General can seek his extradition.
Thailand has extradition treaties with 16 countries including the United States, United Kingdom and Northern Ireland, Canada, Belgium, China, South Korea, Indonesia, Australia, the Philippines, Cambodia, Hong Kong, Laos, Bangladesh, Fiji, Malaysia and India.
An immigration record had shown Vorayuth left Thailand on April 25 for Singapore, where his private jet reportedly remains. It was believed he left Singapore for another destination on a commercial flight.