Thames Valley Police has warned hate crime will not be tolerated following two further religiously-motivated acts at Maidenhead Mosque.
On Monday, a piece of bacon was posted through the Holmanleaze mosque's letterbox, while 'England till I die' graffti was sprayed on nearby tarmac last week.
It comes after stones were thrown through a pane of glass at the mosque on May 22 - the night after Drummer Lee Rigby was attacked and killed in a suspected Islamist attack in Woolwich.
Windsor and Maidenhead LPA area commander Simon Bowden said: "The behaviour of a very small minority is causing concern within the local community.
"Thames Valley Police view all types of hate crime seriously and will not tolerate this appalling behaviour by small minded individuals. The local Muslim community play an important part in the fabric of our community, as do other faiths."
Maidenhead neighbourhood inspector John McKee added: "The Holmanleaze mosque is highly respected locally.
"We've received much support over the years from them for various community events and issues. I find it deeply saddening that such genuinely nice people could be abused in this way."
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