A Spanish teenage student was robbed after a bucket was put over her head as she walked along a public path.
The 13-year-old girl was on the pathway underneath Teville Gate car park, walking towards Broadwater Bridge in Worthing at about 7.30pm on Saturday when the confrontation happened.
A girl approached her, put the bucket over the teenager's head and then took her mobile phone.
The victim asked for it back and the suspect gave it to her but then demanded money.
The teen gave her £10 before running off.
A man walked past while this was going on did not stop to help.
The suspect is described as white, aged about 16 with fair, shoulder-length wavy hair. She had a pale complexion, was thin and was wearing a blue and purple short sleeved T-shirt-style top, black jeans and black Converse-style trainers.
She was in a group of five girls and two boys.
Anyone with information or who saw the incident is asked to contact police by emailing email@example.com or phone 101 quoting serial 1577 of 23/08.