An appeals court on Wednesday upheld a ruling against the labor union of Ssangyong Motor Co., the local unit of Indian auto conglomerate Mahindra & Mahindra Ltd., for holding unauthorized strikes that damaged the company's production.

The Seoul High Court ordered 139 unionized workers to pay a total of 3.3 billion won ($2.8 million) to the company for holding unauthorized strikes from May to August in 2009.

The strikes took place after Ssangyong Motor cut over 2,000 jobs through a voluntary retirement program after it was put under court receivership in the aftermath of the 2009 global financial crisis. About 180 workers were also fired, many of whom filed a lawsuit against the automaker, demanding they be reinstated.

A lower court, however, did not recognize the legitimacy of the strikes and ordered the union to take responsibility for 60 percent of the loss incurred by them, estimated to be 5.5 billion won.

Kim Deuk-jung, head of the Ssangyong Motor union, claimed the ruling seems to unfairly represent the company's interest.

"Considering a series of conservative rulings recently made by the country's judiciary, we are skeptical that an appeal would make the situation any better," Kim said.

Ssangyong said it will first analyze the ruling before taking any further action.

The automaker based in Pyeongtaek, south of Seoul, was purchased by India's Mahindra & Mahindra in 2011. (Yonhap)