Jewellery and watches have been stolen in two burglaries which police believe are linked.
Both burglaries happened between 9.30am and 2pm on Friday, June 12.
In both cases, the offender gained entry via a rear window having climbed a fence.
Once inside, untidy searches were carried out and jewellery including rings, necklaces and watches were stolen.
The first burglary happened in Culbertson Lane, Blue Bridge, and the second in Bertram Close, New Bradwell.
Officers would like to speak to a man seen acting suspiciously at around midday. He is aged around 25, is 5ft 6ins tall, of medium build, and was seen running through Blackwood Crescent.
Investigating officer Det Con Chris Oakman, from Milton Keynes Local CID, said: “The two premises are linked by a redway that runs through Blue Bridge and up to New Bradwell before continuing to Stone Pit fields in the Oakridge Park area.
“We believe these offences may have been committed by the same person, and they almost certainly used the redway. I am keen to speak to anyone who saw anybody acting suspiciously on this pathway around lunchtime on June 12.”
Anyone with information should contact Det Con Oakman on 101 or Crimestoppers anonymously on 0800 555 111.