Cha Seung-won returns to Korea for health reasons

Korean actor Cha Seung-won [Taewon Entertainment]

Actor Cha Seung-won, who departed for Japan over the weekend to film upcoming TV series "Athena," has returned to Korea following a deterioration in his health.

An official with the show's producer explained that the model-actor flew back to Korea on September 13, a day after he had left for Japan, and is currently being treated for his illness.

"We will decide on when he will be returning depending on the pace of his recovery," an official from the show explained. Cha's condition has not been revealed.

Meanwhile, "Athena" is currently being filmed in Japan with Cha's shooting schedule and parts of the script modified.

The show, the spin-off to last year's blockbuster drama "IRIS," is about terrorist acts and threats against the Korean Peninsula and the whole world.

Filmed in six different countries including Japan and Italy, "Athena" features a star-studded cast of Jung Woo-sung, Soo Ae, E Ji-ah, Kim Min-jong and Choi Si-won of idol group Super Junior.

The action series will begin its run in November.