Wan Yubamrung, son of veteran politician Chalerm, reported to police on Monday to answer an arrest warrant issued for the alleged assault of a man outside a pub in April.
Mr Wan turned himself in to Crime Suppression Division chief Pol Maj Gen Maitree Chimcherd and was formally charged with injuring Panuwat Punnarattanakul outside Demo Pub in Soi Thong Lor on the night of April 23.
The Southern Bangkok Criminal Court approved an arrest warrant for him on Thursday.
The Pheu Thai Party member and four friends were accused of punching and kicking Mr Panuwat. Yossapat Saphanchtai, who was with Mr Wan, allegedly also threatened him with a pistol and fired shots into the sky.
Mr Panuwat registered a complaint with Thong Lor police station.
Mr Panuwat, whose parents run the Mae Thong Suk gold shop, had quarrelled Mr Wan's son, Achawin, in Singapore and CSD police suspected that was the motive for the attack when Mr Wan and his son met him at the pub that night. (continues below)
Mr Achawin was at the scene when his father allegedly attacked Mr Panuwat.
The Yubamrung family is heavily involved in politics under the Pheu Thai banner, with their stronghold in Bang Bon and other districts of Thon Buri.
His father, Chalerm, later came to visit him at the CSD office and refused to talk to the media.
