A man targeted in an apparently unprovoked attack suffered a bleed to his brain and had his jaw broken, police have said.
The violent assault happened at Plantation View in Limavady on Sunday shortly after 2.40am.
The PSNI only released details of the incident yesterday.
Police arrested a 30-year-old man at the scene.
He has since been released on bail.
Detective Sergeant Wallace said: "Shortly after 2.40am, it was reported that a male had been pulled out of a taxi and violently assaulted by another male.
"As a result of this seemingly unprovoked assault the victim in this case has suffered a bleed to the brain and a suspected broken jaw."
Anyone who was in the area at the time or who witnessed anything suspicious is asked to contact the police on 101 or Crimestoppers on 0800 555 111.