SEOUL -- South Korean boy band EXO launched their fourth studio album called "The War" on Tuesday, which they said was influenced by other music genres such as electronic dance music and reggae.

The lead single "Ko Ko Bop" combined the "tropical feeling" of reggae with the fast pace of electronic dance music, EXO member Baekhyun said at a news conference ahead of the album's online release on Tuesday.

"It can be called a challenge for us. It's a new genre we are trying," he said.

More than 80,000 copies of the nine-track album have been pre-ordered ahead of its release on online music service websites.

Formed in 2012, EXO earned global success with their first studio album "XOXO". Its hit song "Growl" was picked as the best K-pop song of 2013 by Billboard.

The group's three previous albums have each sold over one million copies.

The band, which topped the 2016 Forbes Korea Power Celebrity list, will host a live show on the country's largest web portal later on Tuesday, among other events to promote the album.