The trial of seven men accused of vote-rigging during an election campaign in Bradford is expected to last three months with up to 300 witnesses being called.

It is likely to take place next autumn and could be in Manchester subject to the availability of a large courtroom equipped to allow pages of evidence presented by computer disc.

Former Conservative parliamentary candidate Haroon Rashid, who stood in Bradford West at the 2005 General Election, is at the centre of the allegations, alongside former Conservative Bradford councillors Jamshed Khan and Reis Khan.

The three men made their first appearance at the City's crown court yesterday.

Alongside them in the dock were their co-accused Alyas Khan, Mohammed Rafiq, Mohammed Sharif Sultan and Tahir Mahmood.

The seven are charged with conspiring to defraud Bradford Council's registration officer over falsely completed applications to vote by post during a three-year period in the run-up to the May election.

They were all closely linked to the Conservative Party at the time, with many being official members.

One of the defendants - Alyas Khan, 49, of Hilton Road, Bradford - was the Bradford West Conservative Association's deputy chairman.

Prosecutor Mark Ainsworth told the Recorder of Bradford, Judge Stephen Gullick, that there would be 25 to 30 files of paperwork to serve, which will take place in January.

The court heard that there will be a large number of witnesses, between 200 and 300, meaning a lengthy three-month trial.

Jamshed Khan, 62, of Russell Street, Bradford, and Reis Khan, 38, of Whetley Hill, Bradford, represented the City and Manningham wards respectively. The pair both lost the party whip following their arrests.

Rashid, of Richings Way, Richings Park, Iver, Buckinghamshire, was unsuccessful in his parliamentary campaign, losing by about 3,000 votes to sitting Labour MP Marsha Singh. Jamshed Khan worked for Rashid at the time.

Rafiq, 67, who appeared in court with an interpreter yesterday, is of Cecil Avenue, Great Horton, Bradford; Sultan, 49, is of Toller Lane, Bradford; and Mahmood, 40, is of Great West Road, Hounslow, Middlesex.

West Yorkshire Police began the investigation into voting patterns and postal votes two years ago in conjunction with the Council.

The returning officer at the time, Philip Robinson, highlighted 252 possible suspect postal votes and applications. They were then examined by the police in the biggest investigation of its kind in the country.

The defendants will next appear on April 7, 2008, when a date and venue will be fixed for the ensuing trial.