A 70-year-old man who was injured when his house was robbed, died in hospital in Nottingham at around midnight last night.
Police named the man as Sonny Grey of Westwick Gardens, Lincoln.
Officers have launched a murder enquiry and they are appealing for anyone with any information to come forward and help them with their enquiries.
The incident took place between 6.30pm and 7.45pm on Saturday, October 29 at the man’s house in Westwick Gardens.
Three potential suspects are being sought.
All are white men and all are around 6ft tall. They were all wearing dark coloured hoodies.
It is believed they entered the house, attacked Grey and stole jewellery and cash.
DCI David Wood said: “Our thoughts are with Mr Grey’s family and we are appealing for the community to pull together and help us with our enquiries.
“We are unable to release details of exactly how Mr Grey died at this time, but he was subjected to a disturbing level of violence and his injuries were extensive.
“The offenders left the scene with some jewellery and possibly an amount of cash.
“We need anyone who thinks they have any information at all on this incident to get in touch with ourselves, or Crimestoppers anonymously and help us with our investigation.
“At this stage we are treating this incident as isolated and there is not thought to be any threat to the wider community.”