A council has apologised "unreservedly" after a letter was sent directing residents to a hardcore porn website.

The letter, urging people to check their eligibility to vote, contained the rogue website address and a resident discovered the error when he typed the address into his web browser.

Babergh and Mid Suffolk District Councils apologised for the "unacceptable mistake" which it blamed on a mail merged form.

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"Sending out this web address was absolutely not our intent and we apologise unreservedly to anyone who received it," said Michael Evans, strategic director at the authority.

"It is unfortunate that the mail merged form produced for Mid Suffolk from the anonymous data on our system has led to this unacceptable mistake.

"It should not have happened and we are putting it right.

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"The forms had been hand-delivered and although only 80 were affected in Claydon and Barham, as soon as the mistake was brought to our notice we stopped their delivery.

"There will be a letter of apology sent out to those who received the wrong information as soon as possible and once again we apologise for this error."