The injury of a 33 year old man while in police custody is under investigation by the provinces police watchdog.
According to the Special Investigations Unit, the man was arrested by Thunder Bay police around 7:30 p.m. on Tuesday in front of a May Street convenience store.
He was then taken to hospital where he was diagnosed with a serious injury.
Two investigators have been assigned to the case, which is in its preliminary stages.
Anyone who may have witnessed the interaction or has video of is is asked to contact the SIU.