Police were questioning a man today about a brutal attack on a former IRA prisoner which left him critically injured and on a life support machine.
The man handed himself in to police at the Grosvenor Road police station in Belfast yesterday after police made two attempts to arrest a suspect.
Frank McGreevy (51) was discovered by his 15-year-old son in the living room of his ground floor flat at Ross Street in the Falls Road area on Saturday evening.
Police discovered a pickaxe handle and blood splattered throughout the flat after Mr McGreevy was bludgeoned about the head.
McGreevy was jailed for life for murder in the 1970s and served around 20 years before being released.
Police Service of Northern Ireland acting detective superintendent Jeff Smyth said: "There has been extensive blood found throughout the dwelling and signs of sustained serious attack.
"There are marks on the walls and blood on the floor and upturned furniture. You can imagine how bad it was."
He added: "This was prolonged, sustained violence, possibly with baseball bats or a pickaxe handle."
He appealed for anyone with information or who saw a Volkswagen Golf - registration AEZ 3796 - which was stolen in Dunville Street and abandoned in Dera Foster Walk to contact them.