Detectives believe Justyna Kalandyk died after being hit by two lorries and two cars as she used a pedestrian crossing in Tulse Hill, south London while the lights were green for traffic.
The 29-year-old was originally from Poland but had been staying with relatives in Wandsworth.
A post-mortem examination gave a provisional cause of death as multiple injuries and an inquest is due to open on Wednesday.
The Metropolitan Police said the drivers of all four vehicles which are thought to have struck Ms Kalandyk have been spoken to.
Among the drivers brought in for questioning was the 49-year-old driver of the first lorry, who was interviewed under caution; and the 52-year-old male driver of the second car who was arrested on suspicion of causing death by careless driving and released under investigation.
The driver of the second lorry and the driver of the first car involved in the collision have been spoken to by officers, but have not been arrested.
The driver of a third car has been traced and is being treated as a "significant witness", according to the Met.
The force said a number of witnesses have come forward to speak to them, but is keen for anyone else who was in the area at the time to get in touch.
Detective Sergeant Alastair Middleton, from the Roads and Transport Policing Command, said: "Even though we have traced all the vehicles that we believe were involved, I continue to appeal for anyone who witnessed the collision and the moments afterwards to contact us immediately.
"We want to hear from anyone who travelled from the South Circular junctions of Norwood Road going towards the junction of Brixton Hill between the hours of 06:30hrs and 07:00hrs on the day of the collision.
"We are particularly interested in any dashcam footage that may have captured some of the incident, before or after the collision."
Anyone with information or footage is asked to contact the Serious Collision Investigation Unit at Merton on 020 8543 5157 or contact via @MetCC.