Thieves were thwarted after an alarm alerted a school caretaker to an attempted break in at a Bury St Edmunds school this week.
Offenders cut a hole in a perimeter fence at Howard Middle School and damaged two windows on a roof on Tuesday morning between 9.10am and 10.10am.
The school caretaker was alerted and disturbed the offenders who made off.
Police are appealing for witnesses to the break in who should contact Pc Emma Bartle on 101 or Crimestoppers 0800 555111.
The intruders damaged a window mechanism on one of the windows on the roof.