Video: Four more now hunted over shopkeeper murder

Two 17-year-olds and an 18-year-old were arrested on Thursday over the death of Gurmail Singh, 63, who was attacked by robbers in his store in Cowcliffe on Saturday evening.

Mr Singh suffered serious head injuries - probably inflicted by a hammer - and died in hospital early on Sunday morning. He was struck at least nine times in the attack.

Detectives are looking for four men in their early 20s or late teens. Speaking outside the shop on Thursday, Detective Superintendent Dave Pervin of West Yorkshire Police said he still needed information from the public. He said: "Anyone who has any information or suspicions that will assist the investigation should continue to contact the police and share that information."

DS Pervin made a direct appeal to those who attacked Mr Singh, and said: "They know who they are. The spotlight is already directly upon them and I call on them to do the right thing and hand themselves in now before we knock at their door and arrest them."

Local people who have CCTV operating in the area have been urged to come forward. DS Pervin said the arrests were made by police "acting on information coming in to detectives".

The shop is in a quiet area of Huddersfield where local people say crime is not a major issue.

Around 30 bunches of flowers have been laid outside Mr Singh's home, which is just a short distance from his shop.

One tribute read: "In memory of a gentle gentleman."

One, apparently written by a young child, read: "You were a nice man. Very kind all the time. Helpful. Shouldn't have been killed. You had a nice shop."