German auto giant Mercedes-Benz said that it has suspended sales operations at a Chinese dealership pending an official investigation into a customer complaint that went viral, in a statement released on Tuesday.

The company apologized Tuesday over the ordeal of a Chinese customer in the city of Xi'an who alleged mistreatment by an authorized dealership in a viral video that triggered consumer outrage.

The customer said in the video that she purchased a new Mercedes from the authorized dealer only to discover afterward that it was leaking oil on the showroom floor. The woman also alleged in later media interviews that she originally wanted to pay cash for the car but was pressured by the dealership into taking out a loan that came with high fees.

The customer's complaints have sparked a flood of supportive online comments by Chinese web-users, with many relating their own consumer horror stories. The oil-leak scandal has since become a symbol for consumer rights protection.

"We're very sorry for whatever happened," said Hubertus Troskas, a board member and head of China operations for Daimler, Mercedes' parent group on Tuesday at the Shanghai Auto Show. He admitted that the incident has not been dealt with properly.

"There is good consumer protection in China and we want all of our dealers to work to the letter of the law and the ethics of our brand," Troskas said.

Authorities in Xi'an, capital of Northwest China's Shaanxi Province and Daimler have already announced investigations.

A local investigative team has started a "full investigation" into actions that potentially violated laws and market regulations such as collecting financial services fees, according to media reports.

The China Banking and Insurance Regulatory Commission (CBIRC) announced Monday that it had directed its branch in Beijing to launch an investigation into Mercedes-Benz's auto financing unit for possible wrongdoings in collecting financing service fees.

(With inputs from AFP)