Hyundai Motor Co. said Sunday it found 97 of its unionized workers in Ulsan and Asan factories logging on to Internet gambling games during work hours.

The country’s No. 1 carmaker said 62 employees at its Ulsan plant and 35 employees at its Asan plant were involved in cyber gambling, betting as much as 100 million won ($92,000) in some cases, according to company officials.

The online gambling was discovered through police investigations on illegal gambling that some of Hyundai Motor employees were involved in. The initial reports were made from inside the company and all 97 workers admitted to gambling, said officials at Hyundai Motor.

The workers at the Asan plant were punished and the remaining 62 at Ulsan will receive firm punishment that follows the company’s regulations. Of the 97 workers, 13 were past or current high ranking members of Hyundai Motor’s labor union.

They were found to have used the computer located at the on-site head offices of the factories to access the Internet gambling games during office hours.

The gambling case is expected to have a negative impact on the labor union’s fight against the automaker’s full enforcement of the time-off system, which imposes a salary cap for full-time unionists.

Hyundai Motor said last month that it did not pay any salary to its 233 full-time unionists in April.

By Cho Ji-hyun (sharon@heraldcorp.com)