Thames Valley Police is making an appeal for information in relation to three robberies, which are believed to be linked in Milton Keynes.
The first incident occurred between 10.45pm and 10.50pm on Saturday (26/3) when three teenage boys were confronted by two men in Bradwell Common Boulevard near to Streatham Place.
The offenders demanded that the victims, all aged 16, handed over their belongings.
One of the victims was chased along Bradwell Common Boulevard in the direction of Conniburrow, while another was shown a knife by the second offender.
The knife was described as silver with a six to seven inch straight edged blade and a black handle.
The offenders are described as white men, approximately 5ft 11in tall of slim build.
They were both wearing dark coloured clothing and black ski masks and spoke with English accents, one of whom with a deep voice.
Nothing was taken during this incident and the victims were not injured.
On the same evening, between 11.30pm and 11.40pm, a 30-year-old man was approached by two men with a similar description along the underpass that runs between the H5 and H6.
Above the underpass is the Cotswold shop and McDonalds.
The two offenders threatened the victim with knives and forced him to hand over an LG phone and two bank cards.
The offenders were both described as white men, in their late teens to early 20s and both approximately 6ft tall.
They both spoke with local accents.
They were wearing dark coloured clothing, with one of the offenders having a beige jacket, black bottoms and black woolly gloves, while the other was wearing a dark jacket and a balaclava.
One of the offenders was holding a beige-handled knife with a blade approximately seven to eight inches long and another offender had a black-handled knife with a four to five inch blade.
The victim was not injured.
At around 9.50pm on Monday (28/5) a third offence occurred on an overbridge near to the YMCA which leads onto Wandsworth Place in Bradwell Common.
The victim was surrounded on this occasion by four men, all of whom had their faces covered with bandanas or balaclavas.
One of the men was holding what the victim describes as a black claw hammer with a black handle and steel shaft.
This suspect had a bandana which was red and black in a cross-stitch design.
He was described as being between 5ft 11in and 6ft tall with a slim build. He spoke with an English accent.
The offender demanded the victim, a 23-year-old man, hand over his property and he gave the offender his wallet, containing £10 and bank cards, headphones and rucksack.
The other offenders were also between 5ft 11in and 6ft tall and had their faces covered.
Investigating officer Detective Constable Katrina Walmsley, of the Investigation Hub at Milton Keynes police station, said: “We are linking all of these robberies together as the descriptions of the offenders are strikingly similar.
“All the victims have been left shaken, but thankfully unhurt.
“With three offences of this nature in a few days, I am hopeful that someone will have witnessed something and can come forward with information.
“We will be reviewing CCTV footage and are making further enquiries, and I would urge anybody with any information to call 101, quoting reference number 43180159873.”
If you have any information relating to this case, please call 101 quoting reference ‘43180159873’, or contact Crimestoppers anonymously.