A 41-YEAR-OLD man is still in police custody after a 57-year-old was killed in what police are describing as a 'vicious attack'. 

The man was arrested after reports of a fight in Cowley Road on Thursday night.

At the time, the 57-year-old was rushed to hospital with serious head injuries and has since died. 

As a result Thames Valley Police have launched a murder investigation. 

READ AGAIN: Police appeal for witnesses after details emerge of assault on Cowley Road

READ MORE: Here's everything we know about the Cowley Road murder so far

The force have the power to hold somebody for up to 24 hours before they have to make a charge or release somebody. 

But police can apply to hold the person for up to 36 if they are suspected of a serious crime, like murder.

The force then have to apply to Magistrates Court for a further extension, called a warrant for further detention, this extends the time in custody to 96 hours. 

The 41-year-old, who was first arrested for causing grievious bodily harm (GBH) but is now being held for murder, is still in police cusody after an extension and a warrant for further detention was granted. 

He is due to be in police custody until tomorrow (22/07) at 5.20pm because Magistrates have granted police an extension of 30 hours. 

Tomorrow evening (22/07) a decision will be made to charge him with murder, another charge or release him.