A parcel delivery worker has suffered a cerebral hemorrhage caused by overwork and fallen into a coma, a couriers' advocacy group said Monday.

According to the group, the 47-year-old employee at Lotte Global Logistics Co.'s branch in Seongnam, just south of Seoul, was sent to a hospital after showing abnormal symptoms, such as stiffness of the body, while he was sleeping at home early Sunday morning.

The courier, surnamed Lim, underwent surgery for a serious case of a cerebral hemorrhage but remained in critical condition in a coma, the group said.

Lim has worked for over two years for the logistics arm of retail giant Lotte Group, where he was reported to face chronic overwork.

Lim had often complained of fatigue as he was made to work six days a week, sleeping only two hours a day, due to a heavy workload, according to the group.

He was assigned to handle around 6,000 parcels per month, or about 250 every day, it said. (Yonhap)