Thieves have made off with a generator and set a lorry and containers alight at a forest site near Lockerbie.
Workmen discovered the theft and damage in Birkshaw Forest at about 08:30 on Tuesday.
A generator and batteries worth about £7,000 had been taken while a lorry and containers valued at about £80,000 were affected by the fire.
Police are keen to hear from anyone who may have been in the area of the forest in the early hours of Tuesday.
They are carrying out inquiries at surrounding farms and cottages to see if anyone saw any suspicious activity.