Deputy Prime Minister Prawit Wongsuwon has given his assurance that police are investigating the alleged assault on political activist Sirawith Seritiwat.
The deputy premier in charge of national security said he has ordered the police to clear up the case and follow up closely on new developments.
Investigators are reviewing video footage from surveillance cameras near the scene of the alleged attack. They are working hard to bring the attackers to justice, according to Gen Prawit.
On Monday, Mr Sirawith vowed to press charges against those he said assaulted him in a supposedly unprovoked attack on Sunday night. Mr Sirawith, known as "Ja New", said on Facebook that he will ask police to file attempted murder charges against them.
The activist claimed he was attacked by several people on Ratchadaphisek Road in Din Daeng district on Sunday night, sustaining injuries to his head and body. His Facebook Live stream showed bruises on his face.
The activist is currently lobbying senators not to vote for Prime Minister Prayut Chan-o-cha -- who has been nominated by the Palang Pracharath Party as its sole prime ministerial candidate -- in today's joint sitting of parliament.
On Tuesday, deputy Crime Suppression Division chief, Nakarin Sukhonthawit said investigators were collecting evidence and interviewing people who might be able to provide information. So far, information on the case has comes solely from police because Mr Sirawith has not been to see investigators to give a statement.
According to police, Mr Sirawith said he was alone when the attack took place. Huai Khwang police station is handling the case.
Pol Col Nakarin urged anyone who might have witnessed the incident to step forward. Police are also interested in knowing where Mr Sirawith was and what he was doing prior to the assault.