Detectives are re-appealing for information in connection with the murder of Satnam Singh in Hayes in 2017.
Satnam was killed three years ago, aged 45, and a Crimestoppers reward of £10,000 remains on offer for any information that leads to the arrest and conviction of the person responsible for his death.
Satnam was attacked in Atlee Road near the junction with Ayles Road as he walked with a friend on Monday, 6 March 2017, at around 22:20hrs.
At the time, a witness reported seeing a man speaking into a mobile phone and following the pair along Ayles Road. A silver car then drove up and a white male got out of the vehicle and attacked Satnam and his friend with a baseball bat. Following the assault the suspect got back in the car and it drove away.
Satnam was taken to hospital for treatment but his condition deteriorated and he died from his injuries on Tuesday, 23 May 2017.
A post-mortem examination gave the cause of death as bronchial pneumonia and a head injury.
His friend, a 28-year-old man, was not seriously injured in the incident.
No arrests have been made to date.
Detective Inspector Andy McDonald from Specialist Crime, who is leading the investigation, said: "Three years on from the death of Satnam Singh the investigation into his murder remains very much active and we continue to appeal for information.
“Sadly Satnam’s uncle, who spoke of his family’s grief back in 2017, has passed away without seeing his nephew’s killer brought to justice. At the time, his uncle spoke of how the whole family were devastated by the attack and how they were desperate to understand why their relative was killed and who is responsible. I hope that three years on someone will come forward with information that can bring this family the peace they deserve.
“Despite the passage of time, we still retain an open mind about why Satnam was attacked. I hope that now, anyone who was reluctant to speak with officers in 2017 may feel able to come forward.
"I would ask anyone who may have witnessed something that night that has played on their mind for the last three years to please get in touch with us. A substantial reward is being offered for information that leads to a conviction of those responsible and I would urge anyone who knows who is responsible to contact police or Crimestoppers without delay."
The reward will be available to anyone providing information via the independent charity Crimestoppers that leads to the arrest and conviction of the person responsible for the murder. To be eligible for the reward your information must be provided to Crimestoppers rather than police.
Anyone with information is asked to call police on 0208 358 0200 and quote Operation Nedderton.
Alternatively to give information and qualify for the reward, Crimestoppers can be contacted on 0800 555 111 or crimestoppers-uk.org. The reward is valid for three months.