HUNDREDS of voters across the North-East have been sent invalid ballot papers due to a series of electoral gaffes.

Election officials were last night in a race against time to reach several dozen voters still to be contacted since the problems were spotted.

The biggest problem was on Wearside, where almost 1,400 voters living on the estates which border two constituencies received the wrong polling information.

In total, 1,007 voters who live in the Houghton and Washington East constituency were told to vote in Sunderland South and 376 people living in Sunderland South received instructions to vote in Houghton and Washington East.

Once the error was discovered, new polling cards were sent to the 1,200 who intended voting in person, but officials have spent several days trying to contact the 200 postal voters affected by the blunder.

The majority had been contacted by last night, but officials were still desperately trying to contact about 40 remaining residents whose votes look likely to be declared invalid unless they can be reached in time.

A spokesman for Sunderland City Council said the problem had arisen due to a recent review of Parliamentary boundaries which had switched a number of households from one constituency to another.

An election hotline for Wearside is available on 0191-553 1141.

Meanwhile, a printing error led to 200 postal voters in Durham North constituency being sent ineligible ballot papers.

Voters in the constituency, which covers Chester-le-Street and Stanley, were sent postal voting packs in which the numbers on the declaration form and the ballot paper itself did not tally.

Officials say the error was caused by a problem at a printers in North Yorkshire.

The problem was spotted when the first postal ballots were returned last Thursday and it was initially feared that as many as one in ten of the constituency's 18,000 postal votes may have been affected.

However, further checks have now revealed the problem to be isolated to a single batch and officials have spent the past six days trying to contact all the voters affected to ensure their votes are cast - although the search was still going on for "a handful" who had yet to be traced last night.

People in the constituency who have queries about their ballot papers are asked to contact the authority's election hotline on 0800 092 9740.