Detectives investigating the death of 47-year-old John Avers in Dagenham last weekend have made four arrests.
Officers stopped a vehicle with the assistance of colleagues from Kent Police on the A2 near Gravesend, at around 11.30pm on Friday 18 September.
One man was arrested on suspicion of murder. He remains in custody at a north London police station.
Two women were also arrested on suspicion of assisting an offender. They have since been released under investigation.
A second man, aged 58, was arrested today on suspicion of murder. He was detained in Southend-on-Sea and remains in custody at a police station in Essex.
Police were called to a car park in Whalebone Lane South at 11.43pm on Sunday, September 13, to reports of a collision between a car and a pedestrian.
Mr Avers was found seriously injured and died at the scene a short time later.
A post-mortem examination found that he died from multiple injuries.
Any witnesses or anyone with information is asked to call police on 101 or tweet @MetCC quoting CAD 8443/13Sep. Alternatively contact Crimestoppers anonymously on 0800 555 111.