The disgruntled owner of a Mercedes-Benz sports car has had it wrecked with sledgehammers to protest over defects and the company's refusal to exchange or take back the vehicle. Wang Sheng began his two-day protest on Tuesday when he had a cow pull his car through the streets of Wuhan in Hubei province after he claimed repeated requests to the manufacturer, the retailer and a consumer watchdog over repossession of the vehicle had failed. On Wednesday, Mr Wang, chairman of the Wuhan Wild Animal Park, ordered five young men to smash up the SLK230 sports car he bought for 700,000 yuan (HK$660,000) a year ago. The demolition was watched by spectators and the press. 'Within three months of purchasing the car, it started to break down. The sales company sent people five times to repair it but soon after it broke down again,' Mr Wang said. 'After the year-long guarantee lapsed, I twice demanded the sales firm and the manufacturer take it back or exchange it but they refused.' Mr Wang bought the car on December 19 last year from the Bing Shi Car Sales Centre of Beijing. He said problems included leaking oil from the steering and defective warning lights. Mercedes-Benz said the car malfunctioned because of the use of inferior oil and there was no problem with the vehicle's quality. The chairman of Bing Shi said: 'Problems arose . . . because the driver went too fast and used the steering too violently. He used low-quality oil.'