Police have issued an e-fit of a man they want to speak to after a 16-year-old girl was robbed at knifepoint in Hastings.
The theft, which happened near the Spar store in St Helens Down on Monday evening, is being linked to two other robberies in the town.
Det Serg Paul Graham said: "We believe this man is local to the area. He is described as white, about 30, slim with short brown or dark hair and about 5' 5" to 5' 9". When he approached the girl in the latest robbery he was wearing a black zip up jacket and a black rucksack."
The teenager was approached by the man at about 6pm. He demanded her phone and when she refused he showed her a knife and grabbed her two carrier bags of shopping.
Det Sgt Graham added: "The girl was obviously shaken by the incident but otherwise unhurt.
"We think the man is linked to two other robberies that took place near convenience stores, all within a few hundred metres of each other. On each occasion the people had been shopping.
"They both happened on Saturday, the first in Victoria Avenue at 7.30pm where the man stole a mobile phone and handbag, the second at 10.30pm at the junction of Victoria Avenue and The Ridge when he demanded a woman hand over her handbag, but she refused."
Anyone with information is asked to call police on 101 quoting Operation Zephyr or the independent charity Crimestoppers anonymously on 0800 555111.