It continued: “He was a loving father of two. He was a good man, a good son, that did everything and more for his family.”
Police said officers had interviewed witnesses and were retrieving CCTV to help establish what happened.
Det Insp Michelle Cordell said: “Our thoughts are focused on Mr Johnson’s family and loved ones, at this incredibly difficult time.
“Our enquiries are moving at pace and we are keeping the family updated as the investigation moves forward.
“We have spoken with a number of witnesses but would urge anyone who has information about what happened that night to come forward and talk to us.”
Two men initially arrested as part of the inquiry were released without charge.
A woman, detained on suspicion of assisting an offender, has been freed on bail.