A man who was fatally stabbed was "kind-hearted" and "would never hurt anyone", his heartbroken mother has said.
Christopher Ritchie, 41, was fatally stabbed in Mitchell Street in Durham at about 08:30 on Thursday.
Durham Police said 30 officers were investigating the murder and were appealing for information.
In a statement, his mother Jean said: "Our hearts are completely broken. Life will never be the same again."
A police spokeswoman said a post-mortem examination confirmed Mr Mitchell had died as a result of stab wounds.
Mr Ritchie's mother said: "Christopher was kind-hearted and generous. He would never hurt anyone.
"He was a loving son, brother and dad and we all love him to bits."
'Desperately seeking answers'
He also leaves behind his sister Beverley, son Robbie, stepsons Joel and Maximus, former partner Faye, brothers Eddie and Lee and niece, Jasmine, the family said.
"Christopher was funny and kind, he would do anything for anyone," his sister Beverley said.
"He didn't have a bad bone in his body,"
"My world has ended without him - I will miss him so much."
Det Ch Supt Adrian Green said: "Christopher's family have been devastated by his murder and are desperately seeking answers as to what happened to him and why."
The force previously said Mr Ritchie was a distinctive-looking man "well known" in the centre of Durham who was on metal crutches when he was killed.