Two men were robbed in separate “vicious” attacks within hours of each other in the same area.
Detectives are investigating whether the incidents in Dalkeith, Midlothian, are linked and have appealed for information.
In the first incident, a group of four men attacked a 23-year-old man who was standing alone at a bus stop on Lauder Road opposite Bruce Gardens at around 12.30am on Sunday.
He was dragged on to a grassed area behind the bus stop where he was robbed of his wallet and mobile phone before being assaulted.
The suspects are thought to be aged in their mid-teens. One was riding a BMX bike while two were wearing hooded tops with the hoods up.
In the second incident, a man was assaulted and robbed as he walked alone on Lauder Road at around 2.30am, near to where the previous robbery took place.
Two men came up behind him and punched him in the head, causing him to drop his iPhone 6.
One of the men picked up the phone while the other demanded that the victim hand over his wallet.
The victim managed to run away from his attackers, who were last seen heading in the direction of Bruce Gardens.
The first suspect is described as white, aged 16 to 20 with short, light hair and a slim build.
His accomplice is also white and of similar age and build. He was wearing a dark hooded top, dark jogging trousers and spoke with a local accent.
Detective Constable Mandy Cummings of Police Scotland said: “Both incidents were particularly vicious and it would appear the attackers were targeting people who were on their own and on foot.
“At this stage we are keeping an open mind that these offences are linked but we need the assistance of the public to ensure the suspects are traced as quickly as possible.
“Anyone who saw them or has information that may assist our ongoing inquiry is asked to call 101, or alternatively information can be passed anonymously through the charity Crimestoppers on 0800 555 111.”
Police are also investigating an incident the previous day in which a woman was knocked unconscious and robbed in Bonnyrigg, Midlothian.
The 21-year-old was walking near the RBS cash machine in the High Street when she was attacked from behind at around 11.30pm on Saturday.
When she woke she found her purse, bank card and cash had been stolen.
She suffered minor head injuries and was treated by the ambulance service at the scene.
The victim believes a man was involved but no description is available as she was attacked from behind.
Detective Constable James Welsh said: “This was an extremely distressing incident for the young woman involved and we’re urging anyone who may have witnessed the incident, seen anyone acting suspiciously in the area at the time of the incident, or who has any information which can help with our inquiries to come forward.”