The damage took place at Redditch Central Mosque on Jinnah Road in Worcestershire as intruders forced their way through a gate and broke into the main building.
It is not yet known if anything was stolen.
"Due to incidents happening nationally targeted patrols have been put in place and these will now be further increased as we will not tolerate mindless attacks of this nature," said Superintendent Kevin Purcell of the North Worcestershire police, in reference to a number of recent attacks on mosques across the region.
His officers have increased patrols in the area and are now guarding the site.
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