Police in San Francisco have released footage of the "brutal" murder of a 44-year-old Briton assaulted in a street robbery.
Paul Tam was walking with his niece on the evening of February 18 when he was attacked with a weapon in the Japantown neighbourhood of the Californian city.
The former website manager at the University of Manchester was critically injured and died on Thursday.
CCTV footage of the incident shows Tam fleeing from a hooded assailant into the middle of the road before he is chased around an oncoming car. He is then knocked to the ground by the offender who makes off on foot with his bag.
Police said they were releasing the video evidence that "captured the brutal murder" in a bid to trace the male offender and a female suspect following the robbery at 8.30pm in Post Street, between Franklin Street and Gough Street.
The suspects are described as a black adult male, 5ft 10in, of heavy build and last seen wearing a dark hoodie and blue jeans, and a black adult female, 5ft 4in, with long dreadlocks or braids up in a ponytail.
In a statement, the San Francisco Police Department said: "SFPD Homicide Investigators are seeking the assistance of the public to identify the outstanding suspects. Please contact investigators if you were in the area of the crime near the time of the crime, observed any suspicious activity, or if you have information regarding the identity of the suspects."
It has previously been reported that Tam's bag contained his passport, money, mobile phone and bank cards, and that he had been staying in a hotel in San Francisco at the time after leaving the UK to look for a new job in California.
A spokeswoman for the Foreign and Commonwealth Office said: "We can confirm the death of a British national on March 24 in San Francisco and we are providing consular assistance to the family at this difficult time."