An incident in Waitrose car park has led to the death of a 75-year-old woman.
It happened at 4.20pm on Saturday, and a number of emergency vehicles attended.
A 44-year-old woman was arrested in connection with the incident, but later released.
The pensioner was taken to hospital but later died.
A Gwent Police spokesman said: "Officers attended a road traffic collision in Waitrose car park on Monnow Street, Monmouth at about 4.20pm on Saturday, December 31, and are appealing for anyone with information or dashcam footage to assist with their enquiries.
"Officers attended, along with personnel from the Welsh Ambulance Service, following a collision between a car and a pedestrian.
"A 44-year-old woman from the Monmouth area was arrested on suspicion of causing serious injury by dangerous driving, she has since been released as our enquiries continue.
"We’re asking for any motorists with dashcam footage that were using Waitrose car park between 4pm and 4.20 pm to contact us."
The spokesman continued: "We would also like to hear from anyone who may have seen a red Toyota Yaris being driven in the car park on Saturday, December 31 to contact us."
You can call police on 101 or send them a direct message on Facebook or Twitter, quoting log reference 2200435393 with any details.
Alternatively, you can call Crimestoppers anonymously on 0800 555 111.