Smoking accounted for more than 80 percent of in-flight illegal acts reported by South Korea's 10 carriers in the past five years, government data showed Tuesday.

In the five years through July this year, 1,509, or 80.8 percent, out of 1,868 illegal acts were related to smoking onboard, according to data from the Ministry of Land, Infrastructure and Transport.

Under South Korean law, a fine of up to 10 million won ($7,500) will be imposed once in-flight smoking, including e-cigarettes, is found.

Smoking during flights is banned as it may ignite fires, wear down the in-flight air filtration equipment and also cause discomfort to other passengers.

Other illegal acts include illegal filming, violence, verbal abuse, and sexual harassment, the ministry said. (Yonhap)