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.
"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.