A stained glass window in St Albans Cathedral was smashed overnight on Monday after a break-in through the education centre in Sumpter Yard.
A brick was thrown through the Grant Memorial Window in the North Transept which was manufactured by Burlison and Grylls and installed in 1897. The window measures 6ft by 4ft and the damage is estimated to be in the region of £10,000.
The vandal(s) got in by climbing over the cathedral railings and into the education centre where they took the door handle off before throwing the brick at the window.
It happened sometime between 10pm on Monday and 6.40pm on Tuesday.
Anyone with any information is asked to contact Pc Ben Kirby on the police non-emergency number 101 or Crimestoppers on 0800 555111.
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