A man wanted in connection with a murder and assault in Northumberland is believed to have travelled to Glasgow.
Officers have released an image of Paul Robson as they bid to trace him over an incident in Linton on Sunday evening.
Police were called to an address in Foxcover at around 8.55pm and found a 47-year-old woman and 15-year-old boy had been assaulted.
The woman, Caroline Kayll, had suffered life-threatening injuries and later died in hospital.
The teenager suffered serious but non-life threatening injuries and has now been discharged from hospital.
Police say he is not related to Ms Kayll or the suspect.
Mr Robson, from Wallsend, North Tyneside, was known to Ms Kayll.
He is described as white, around 5ft 5in, of slim build, bald and wears glasses.
A 58-year-old man has already been arrested on suspicion of assisting an offender and remains in police custody.
Superintendent Paul Milner, of Northumbria Police, said: “This has been a complex investigation that has seen officers carrying out inquiries across the region this week.
“We know that it has caused a great deal of concern, particularly the fact that a suspect in this case has not yet been arrested.
“I want to reassure you that this is being treated as an isolated incident and there is no information that suggests Paul Robson is a danger to the wider public.
“Extensive inquiries to locate Paul have continued in recent days and we are now appealing for help from the public to locate him.
“We would stress that this is a live murder investigation and an incredibly difficult time for Caroline’s family and the teenage boy injured in the attack.
“We would urge people not to speculate on any of the circumstances as it could hinder our investigation.”
Anyone with information about the inquiry can contact officers on the Northumbria Police website quoting log 421 of November 19, by calling 101, or through Crimestoppers anonymously on 0800 555 111.