A fourth person has been arrested in the ongoing investigation into the murder of Tim Hipperson in Richmond last week.

A 31-year-old man was arrested on suspicion of assisting an offender on Sunday, May 23, the Met Police said in a statement updating the public on their progress in the case.

He has since been bailed pending further enquiries.

As the RTT reported previously, 39-year-old Tim died in hospital on Thursday (May 20) after he was stabbed "in the vicinity of the Kings Road" in Richmond on Monday, May 17.

Police were called to the scene just before 4pm, where they found paramedics from London Ambulance Service treating his injuries.

Read more: Three charged over Richmond stabbing death

Tim was taken to hospital, where he sadly died on Thursday morning.

In addition to the 31-year-old arrested on Sunday, three other people have been arrested in the murder investigation into Tim's death.

A 34-year-old man was charged with murder and two counts of being concerned in the supply of Class A drugs, namely cocaine and heroin.

A 35-year-old man was charged with assisting an offender and two counts of being concerned in the supply of Class A drugs.

A 37-year-old woman was charged with assisting an offender.