Two men have been arrested after a man was fatally stabbed when he confronted a gang of moped thieves with his father, according to Scotland Yard.
The attack took place outside their home in Chadwell Heath, East London. The 27-year-old man died following the attack and his 46-year-old father suffered knife wounds, however his injuries are not described as life-threatening.
The two suspects were arrested in the early hours of Wednesday and remain in police custody. Police said they were arrested on suspicion of murder.
After hearing a disturbance outside their home in Gibbfield Close at around 1.25am on Tuesday, the father and son saw a group of up to four men attempting to steal a moped, Scotland Yard said.
They were stabbed in an altercation and the thieves fled the scene without the moped.
The victims were taken to an east London hospital where the younger man was pronounced dead in the early hours of Wednesday. His father remains in hospital.
Scotland Yard announced that they know the identity of the dead man, but are awaiting formal identification.
Detectives from the Metropolitan Police's Homicide and Major Crime Command appealed for anyone who may have seen or heard anything to come forward.
Detective Chief Inspector Andrew Packer said: "Gibbfield Close is a residential street and while there would not have been many people out and about at the time of this attack, it was a warm night and people would have had their windows open.
"I am appealing to anyone who heard, or subsequently saw, anything suspicious to come forward and speak to police."
Any witnesses or anyone with any information is asked to call police via 101 or call Crimestoppers anonymously on 0800 555 111, or visit crimestoppers-uk.org.