Windmill Road in Headington has been closed by police this afternoon.
Officers from Thames Valley Police have been on site since 3.30pm and the road is closed both directions.
It is understood that someone may have been stabbed in the road at about 3pm.
The Road is now full of Scene of crime officers. With Officers on scene guards at both ends of the street directing traffic away from the area being examined by specialist officers.
A 27-year-old man has been arrested on suspicion of attempted murder after reports of a stabbing in Headington, Oxford.
Thames Valley Police have confirmed that they were called at 3pm to reports that a man in his 30s had been stabbed.
He has been taken to the John Radcliffe Hospital with life-threatening injuries.