Police have arrested 15 Chinese and Thai citizens over their suspected links to a string of illegal businesses and phone scam rings, from which they seized assets valued at over 42 million baht.

Their arrest followed a crackdown following a raid on a nightclub masquerading as a car wash in Yannawa district, and the death of a Chinese tourist after a night out drinking at a venue run by Chinese businessmen in Ratchada district.

The suspects were arrested on Wednesday following raids at three different locations across the capital.

Police first raided a house on Soi Kanchanapisek in Prawet district, where they arrested five Chinese nationals and three Thais.

They seized three cars, two motorbikes, 58 bottles of foreign liquor, 13 mobile phones, three notebooks and 7 million baht in cash at the location.

The police then raided a house in Prawet district which is owned by a Chinese national named Lin Yian, where they found Mr Lin's father and two Thais.

Many items, including three cars, a luxury watch, a passbook, suspicious ID cards and passports, as well as 7.5 million baht in cash were seized by police.

At Supalai Oriental Sukhumvit 39, they apprehended four Chinese nationals and seized eight brand-name bags, cigars, playing cards as well as 28 million baht in cash.

A check on Mr Lin's ID card showed that it was illegally produced by a state official in Chiang Mai's Fang district, using the identity of a Thai farmer. Mr Lin also holds Thai and Cambodian passports.

The man is known to run a restaurant near the notorious Kings Romans Casino over the border in Laos.

Police are expanding the investigation to see if there are other state officials, politicians and senior police officers involved.