Detectives are appealing for witnesses after a series of robberies in Woodford Green.
The latest offence occurred on Sunday, January 24 around 4pm in the Roding Valley Park area.
A woman was walking whilst talking on the phone, when a man threatened threatened her with a knife to hand over her phone and the security details.
Luckily some passers-by witnessed the incident and chased the suspect.
He eventually threw the phone on to a path and managed to escape.
The suspect is described as a black man, aged around 18-years-old, and wearing a black hat and black clothing with a possible blue stripe down the side of his tracksuit bottoms.
Police are asking for any witnesses to this incident or anyone with information that may help to call 101 quoting reference 4401456/21
To remain anonymous, call Crimestoppers on 0800 555 111 or contact them via crimestoppers-uk.org.
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