Officers are appealing for information after two vehicles, equipment and kerosene were taken from a council roads depot in Hawick.
The incident happened between 3.30pm on Friday, 16 June, and 5.45am on Monday, 19 June, at the depot on Upper Mansfield Road in the town.
A white Peugeot Partner van, registration NU1 GKK and a white Ford Transit tipper, registration FH16 EKX, were taken, along with a quantity of small equipment worth around £9,000 and 1,000 litres or kerosene.
The Peugeot van was later traced near Hexam in Northumberland. The Ford Transit is still to be traced.
Detective Constable Claire White, of Galashiels CID, said: “Our enquiries are ongoing and we are appealing for anyone in the area over the weekend who saw anything suspicious to get in touch. Likewise, if you have private CCTV or dash-cam footage that could assist with our investigation then please call us.”
Anyone with information should contact Police Scotland on 101, quoting incident number 0571 of Monday, 19 June, 2023.