Four people have this morning been arrested on suspicion of assisting an offender, by detectives investigating the murder of Jon Casey.
The four men, one aged 18, one 19 and two 20, were arrested early this morning in Coventry.
Mr Casey, 35, was found seriously injured in Barrack Road, Northampton, at about 5.30pm on Friday, January 16.
He died in Northampton General Hospital a short time later.
A 19-year-old man was arrested on suspicion of murder on Thursday, January 22, and bailed pending further inquiries.
Det Insp Mark Brayfield said: “We believe Mr Casey had been involved in an altercation with two men shortly before he was found in Barrack Road and I would still like to speak to anyone who may have been in the area at the time to contact us.
“We would particularly like to speak to a woman who was pushing a buggy in Hester Street at about 5.15pm, who we believe may have had a brief conversation with the offenders.
“She may not realise the significance of this encounter, and so I would urge her to please contact us.”
Witnesses, including the woman with the pushchair, or anyone with information about this incident, is asked to contact police on 101 or Crimestoppers anonymously on 0800 555 111.