Police say the driver of red car may hold crucial information about the murder of a man found fatally injured in a street.
Officers found a 66-year-old man with serious injuries following an assault in Gaunt Street at around 11pm on Monday. He died at the scene.
A 32-year-old man arrested on suspicion of murder remains in custody.
Lincolnshire Police are appealing for witnesses. A spokesperson said: "We would particularly like to trace the driver of a red car who may have crucial information to help our investigation.
"We don't have a make and model, so we ask that anyone who was driving a red car in the Gaunt Street area between 7pm on 5 June and 12.30am on 6 June to get in touch."
Det Ch Inspector Jen Lovatt said there was not thought to be any ongoing risk to the public.
"I am satisfied that, at this moment, we do not need to look for anyone else in connection with this investigation," she said.
"I want to make clear that we do not think there is any wider threat to the public."
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