A man was punched in the face for his wallet, but the would-be thief left empty handed.
The 48-year-old was walking along Chadds Lane towards Waterside when a man asked him if he had his wallet while at the junction with Ambridge Grove.
The victim was then punched in the face, before running off towards a phone box in Chadds Lane.
He was followed by the offender before fleeing towards Ambridge Grove at about 11.20pm on Tuesday.
The offender is white, in his late thirties, about 5ft 9ins, with short dark hair and dark facial hair. He was wearing dark clothing and spoke with a local accent.
Nothing was stolen during the incident.
The victim sustained facial injuries but did not require hospital treatment.
Investigating officer, Det Con Wendy Cissell based at Milton Keynes police station said: “I would appeal to anyone with any information to contact police immediately via 101.
“I am particularly interested in hearing from anyone who recognises the description of the offender, or has information about two vehicles that travelled past the incident. One of the vehicles is possibly a taxi and the other might be a silver Vauxhall Corsa.
“If you are the drivers of those vehicles or know who is then please contact police.
“If you don’t want to speak directly to the police you can contact Crimestoppers anonymously on 0800 555 111 or online at www.crimestoppers-uk.org.
“No personal details are taken, information is not traced or recorded and you will not go to court.”