The incident was reported just before 6 p.m. near 9th and Grand. The officer was responding to an agitated individual and was trying to calm him down when he was stabbed in the chest right above the vest line.
Police tell FOX4 a suspect has been taken into custody.
The officer was taken to the hospital in critical condition. He has since been upgraded to stable.
Police said the stabbing was not related at all to the protests happening at the Country Club Plaza over the killing of George Floyd while in Minneapolis police custody last week.