BEIJING (AFP) - A wealthy Chinese Maserati owner hired four sledgehammer-wielding men to smash up his US$420,000 (S$522,400) supercar in protest at poor customer service, reports said on Wednesday.

The car owner, identified only by his surname Wang, had the group attack the Maserati Quattroporte at the opening of an auto show in the eastern city of Qingdao, in Shandong province, the Qingdao Morning Post said.

Video images showed the men going about their task with gusto, leaving the vehicle with a shattered windscreen and mirrors, the grille broken and dents to the bodywork, draped in a banner accusing the Italian manufacturer of poor decision-making.

Mr Wang bought the luxury car in 2011 for 2.6 million yuan, the report said - around 100 times the average income of Chinese urban residents last year.

But problems first arose when he took it back to the dealer for an unspecified repair, with staff charging him for new spare parts despite using used ones, the paper quoted Mr Wang as saying. It later failed to fix a problem with a door and scratched the vehicle, he added.

"I hope foreign luxury car producers acknowledge clearly that Chinese consumers are entitled to get the service that is commensurate with the brand," Mr Wang said.

China is the world's largest auto market after overtaking the US in 2009.

It is also a key market for luxury brands, with the country's growing ranks of mega-rich splashing out on fancy cars to show off their wealth.

But buyers enraged by bad service have carried out similar actions previously.

In 2011, a businessman also in Qingdao reportedly destroyed a three million yuan Lamborghini after failing to get problems with the engine and other car parts repaired properly.