THE voting chaos that left hundreds of people queuing outside polling stations when ballot boxes closed will never happen again, election watchdogs vowed yesterday.

The Electoral Commission is carrying out an inquiry into what happened – which has been roundly condemned by the leaders of the main parties – and has called on people affected to contact them.

High turnouts caused problems at polling stations in cities including London, Sheffield, Manchester, Liverpool and Newcastle, with some polling stations running out of ballot papers and others locking people outside.

There were angry scenes in Hackney, east London, where would-be voters staged a sit-in after they were told they could not vote, while in Nick Clegg’s constituency of Sheffield Hallam, students tried to prevent ballot boxes being taken to the count after they were turned away.

Electoral Commission chairwoman Jenny Watson described the present voting system as Victorian and at breaking point.

She said: “We will obviously be talking to returning officers.

But we want to hear from voters who experienced problems on polling day – whether they were unable to cast their votes, or encountered any other difficulties.

“This will help us identify what went wrong and what needs to change so it never happens again.”

Human rights campaign group Liberty said it was also looking into allegations that hundreds of potential voters were disenfranchised.

People who were prevented from voting were urged to contact Liberty “with a view to further action”.

The Electoral Commission said it would look into the planning and management by local returning officers, as well as their responses to the problems. Its review will be published by the end of next week at the earliest.

After results in 649 of the UK’s 650 constituencies had been announced, national turnout stood at 65.1 per cent, up from 61.4 per cent in 2005 and 59.4 per cent in 2001.

In some places, including two polling stations in Newcastle, voters were ushered inside before 10pm when the doors had to be shut, while at one site in Lewisham ballot papers were handed out to the queue before the deadline.

But there were reports in the Manchester Withington constituency of people queuing for more than two hours before being turned away because the polls had closed.