The state media watchdog said Sunday that it will swiftly review punitive measures against public broadcaster KBS for airing an opera performance featuring Japan's national anthem that many South Korean viewers found inappropriate for Liberation Day.

A series of complaints have been filed since KBS' airing of "Madama Butterfly," an opera featuring traditional Japanese attire and Japan's national anthem, on Liberation Day that commemorates the end of Japan's 1910-45 colonial rule of the Korean Peninsula.

The Korea Communications Standards Commission said that it has received 28 complaints from viewers and plans to designate the issue as an agenda item for expedited review during the plenary meeting scheduled for Monday.

Once designated as an item for expedited review, the commission will determine punitive measures within two weeks, potentially including heavy penalties.

KBS aired a recorded performance of the opera, which was filmed at the Seoul Arts Center in late June.

In 2014, the commission issued a warning to another broadcaster, JTBC, for playing the Japanese anthem while introducing a Japanese panelist.

In a separate agenda, the commission is also expected to review punitive measures against JTBC for airing security camera footage of an unrelated individual riding an electric scooter, mistakenly identifying the person as Suga from the K-pop supergroup BTS.

Suga has been booked for investigation after being found lying on the ground after falling off his electric scooter while driving under the influence of alcohol in the Yongsan district of central Seoul earlier this month. (Yonhap)