Sussex Police said two separate robberies which saw young men threatened with a knife in Brighton on Saturday (February 2) could be linked.
The first incident took place outside Brighton station on Queens Road at around 6pm.
An 18-year-old man’s iPhone was stolen when he was approached by four men and threatened with a ‘what he believed to be a knife’, police said.
Three of the suspects were described as black and one was of Indian ethnicity.
A second robbery then took place at 9pm outside Subway in Queens Road.
Police said the 17-year-old victim was with his friend when they were approached by a group of five black men and one white man.
The victim was threatened with a knife and ran off, but his friend was then surrounded by the group who demanded he hand over his silver necklace, officers said.
Sussex Police said an 18-year-old man from Brighton was later arrested on suspicion of the second robbery and released under investigation.
The force added a 17-year-old boy also from Brighton was detained on suspicion of both robberies and released under investigation.
Detective Constable Charlotte Dowling-White said: “We are linking the two robberies and are appealing for witnesses as we are still looking for outstanding suspects. If anyone has any information about the robberies please contact us.”
Contact police on 101 quoting serial 912 of 02/02 with any information.