Four people have been arrested in Britain on suspicion of murdering a 23-year-old man with learning difficulties who was battered unconscious in an apparently motiveless street attack by a gang of youths.
Brent Martin suffered multiple injuries and later died in hospital after what police said was a "savage and prolonged attack".
Detectives said a murder inquiry is now underway after Mr Martin died earlier today in hospital.
Three male teenagers, one aged 16 and two aged 17, and a 21-year-old man have been arrested in connection with his death and are in custody.
An appeal has been made by police to trace a number of other youths thought to have been involved in the attack on Thursday night in Baxter Road, in the Town End Farm area of Sunderland.
Detectives hunting the youths have now urged parents to think about what their children were doing on the night of the attack.
The attack happened around 10pm on Thursday night and Mr Martin, a local man, died early today in Sunderland Royal Hospital.
PA