A 46-year-old man was knocked unconscious and left with serious facial injuries after being attacked close to a pub where he had been celebrating the turn of the year.
Police are now appealing for witnesses to the assault which happened shortly after the man left the Tawny Owl pub in Walnut Tree at 1am.
The assault left him unconscious and with serious facial injuries, requiring surgery.
There is no description of the offenders.
Anyone who witnessed the assault or who has any information is asked to contact investigating officer detective constable Gary Huff from Milton Keynes Force CID on 101.