Georges St-Pierre tears ACL

TORONTO -- Former UFC welterweight champion Georges St-Pierre tore ligaments in his left knee in training and will need surgery.

St-Pierre made the announcement on Twitter:

The 32-year-old Montreal fighter remained in training after vacating the title in December and plans to return to MMA at some time. He had reconstructive surgery on his other knee in December 2011 after tearing his ACL during a wrestling drill.