The gardens at a popular Norfolk Broads site have been closed for the "foreseeable future" due to ongoing vandalism and the theft of a donation box. 

How Hill Trust, near Irstead on the River Ant, announced that it had closed its "secret gardens" to the public following a spate of vandalism that saw its donation box stolen and a knife left on the property.

According to the trust, the theft happened on the evening of Thursday, April 13, and involved the use of an adjustable spanner and a screwdriver to remove it from its fixing. 

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The box had been in place for more than 10 years and was believed to have contained a fair amount of money following a busy Easter weekend. 

How Hill Trust director Simon Partridge said it was not the first time such a thing has happened, with a carving knife found on the property during the Christmas holidays which he said was "rather alarming".

The public car park remains open but the gardens will stay closed until a new donation box can be installed which the trust hopes will be in the next 10 days.