The Independent Office for Police Conduct (IOPC) is investigating police’s prior contact with a woman who died in a crash in Burton village near Lincoln in the early hours of Wednesday morning.
As previously reported, a 25-year-old female pedestrian died after she was hit by a van at around 1.25am on March 4 on Middle Street in Burton.
Police said the driver of the van was not injured, but the road was closed in both directions for more than eight hours.
There were no arrests.
The IOPC is now investigating the matter following a referral from Lincolnshire Police.
It understands the force attended an incident involving the same woman during the evening of Tuesday, March 3.
An IOPC spokesperson said: “We can confirm we have begun an independent investigation into earlier Lincolnshire Police contact with a 25 year-old woman who died in a collision in Burton yesterday morning, March 4.
“We understand the force had attended an incident involving the same woman on Tuesday evening.
“Following a referral from the force we have begun gathering information as part of our investigation.”
The IOPC oversees the police complaints system in England and Wales and investigates the most serious matters, including death following police contact. It is independent and makes its decisions “entirely independently of the police and government.”