A man needed hospital treatment after being attacked with a substance as he walked in a subway in Wearside.
The 30-year-old was making his way under the A1231 in Musgrave Terrace, in Washington when he was approached by a gang.
He had a noxious substance squirted in his face causing injuries.
His attackers ran off after being disturbed by members of the public.
The attack happened about 1.30am on Friday September 11.
The injured man was taken to the Royal Victoria Infirmary where he is detained for treatment.