Zahwa Salah Muktar was found seriously injured in Chadwell Heath Lane at around 5.30am on August 16.
The 27-year-old was pronounced dead at the scene shortly after.
A 35-year-old man was arrested on the evening of August 17 on suspicion of assisting an offender.
This is in addition to a 35-year-old man who was arrested on suspicion of murder, alongside a 21-year-old and 22-year-old who were arrested on suspicion of assisting an offender.
All four men remain in police custody.
Detectives believe this was an isolated incident and that those involved were known to each other.
Detective Chief Inspector Phil Clarke, who is leading this investigation, has since confirmed that Zahwa was in the company of a group of people in the vicinity of Palatine Road in the early hours of August 16.
He added: “Our thoughts remain with Zahwa’s family and friends at this undoubtedly difficult time for them all.
“We are keen to understand the events prior to Zahwa’s death.
“We would like to speak with anyone who was with Zahwa and who may have any information that may help police understand her movements on that day.”
Superintendent Clare McCarthy from the policing team in the local area said: “This was a tragic incident, and our thoughts are very much with Zahwa’s family and loved ones.
”We understand how important it is to address any concerns within the community and we are working closely with our partners, including local authorities, faith leaders, and community representatives, to provide support and reassurance.
“The community has been deeply affected by Zahwa’s death, and we are committed to working together with partners to ensure people feel safe, heard, and supported.
“I would continue to urge anyone who has information, no matter how small it may seem, to come forward and speak to us.
“Your information could be crucial in helping officers understand exactly what happened and in securing justice for Zahwa and her family.”
Anyone with information is asked to contact police by calling 101 or online, quoting CAD 1625/16AUG.
Alternatively, you can contact the independent charity Crimestoppers anonymously on 0800 555 111 or by submitting an online form.