Election staff in Great Yarmouth are having to be extra vigilant today after 400 cards were sent out in error to teenagers under the legal voting age.

Although the blunder was soon spotted and their names struck from the list of eligible voters, a close eye is being kept on affected stations and staff fully briefed.

Among those receiving the surprise invitation in the post was 17-year-old student Kasie Fennell from Great Yarmouth.

Despite being under the legal voting age – she is 18 in July – she was among hundreds of youngsters born in 1996 being asked to take part in the election.

Her mother Tessa, 38, of Perebrown Avenue in the Yarmouth North ward where a borough council seat is being contested, said she was 'bemused' by the blunder.

'I was a bit mystified,' she said. 'But it is also a bit worrying because it is an extra 400 votes for someone. About a week later I got a letter through saying there had been a computer error and that everyone that was born in 1996 got a voting card whether or not they were eligible to vote.'

A spokesman for Great Yarmouth Borough Council said: 'The returning officer became aware in early May that polling cards for this month's elections had been wrongly posted to about 400 people who will not have reached the legal voting age of 18 by polling day on Thursday, May 22.

'These 17-year-olds were on the electoral register because they will all be 18 this year, between Thursday and December 1, when the register expires. However, they will not be old enough to vote on Thursday.

'Letters explaining the situation were immediately sent to all those affected, and their names have been struck out on the list of eligible electors which will be at polling stations. The borough council has now fully investigated the problem, which was caused by an IT issue.'