BRUSSELS (AP) — A passenger train derailed and flipped on its side Saturday near Brussels, killing one person and injuring up to 20 others, a Belgian official said.

Leuven Mayor Louis Tobback said the person who died in Saturday's accident most likely might not have been on the train itself but caught on or near the rails. The accident occurred early in the afternoon as the train left the Leuven station at slow speed in the direction of Brussels Airport and the Belgian capital.

Photos of the accident showed one passenger car lying on its side. Tobback said most of the injured were only slightly hurt.

All train traffic in and out of Leuven, 20 kilometers (12 miles) east of Brussels, was interrupted by the derailing.

Authorities launched an investigation into the cause of the derailing, which was not immediately known.