Detectives were continuing to question a man and a woman today in connection with the Euston handbag killing.
They were arrested in the early hours of yesterday morning in a dramatic raid on an address in West Hampstead, north London, after a police surveillance operation.
The 35-year-old man and 23-year-old woman, both from north London, were together when police burst into the address, Scotland Yard said.
Both are being quizzed over the attack which left Elizabeth Sherlock dying of horrific injuries after she chased handbag thieves out of Euston station in broad daylight on Bank Holiday Monday.
The ‘‘bubbly’’ 42-year-old had leapt on to the bonnet of their getaway car but slipped beneath the front wheels as it sped off.
The battered car was found abandoned near the train station a few hours after the attack.
A Scotland Yard spokesman said: ‘‘The man and woman were arrested by officers working on information received.
‘‘It followed an intelligence-led operation on a premises in West Hampstead.’’
Mrs Sherlock was having a coffee with her husband Peter when the thieves grabbed her bag - containing just £20 - and ran away.
Dozens of people rang the investigation hotline to give information about the incident.
Sources said a number of callers claimed to have identified the culprits.
Mr Sherlock, a 48-year-old computer programmer, said on Tuesday that his wife had acted instinctively when she gave chase to the muggers out of ‘‘a sense of right and wrong’’.
Describing his wife as a ‘‘5ft 2in bundle of energy’’, he made a heart-rending appeal for witnesses to the tragedy.
Mrs Sherlock, of Chiswick, west London, worked on television programmes including Last of the Summer Wine, It’s A Knockout and the Royal Variety Performance.
She had recently finished working on her first feature film - The Four Feathers, a Hollywood production starring Oscar nominee Kate Hudson.