CROOKED political activists could fix a referendum for a "mini-Parliament" in Yorkshire by going from doorstep-to-doorstep gathering unused postal voting forms, it was claimed today.

Tory shadow regions spokesman Bernard Jenkin warned there was a threat of "vote-harvesting" if controversial proposals to ditch ballot boxes were approved.

He insisted fears were great enough for the Government to scrap plans for all-postal voting in the referendum for a directly-elected regional assembly in Yorkshire and the Humber.

In a letter to Local Government Minister Nick Raynsford, he said he was "increasingly concerned" that the referendum would be conducted using a pilot scheme which had "raised serious questions about its security and integrity".

Mr Jenkin said: "If these issues are not addressed, then there is a real possibility of vote-harvesting - unscrupulous organisations canvassing from house to house, collecting uncompleted ballot papers to get the result they want."

He wants the Government to introduce a raft of stringent security measures to prevent election fraud - including tougher punishments for offending, giving the police greater powers of arrest and introducing registration for individuals, rather than households.

The Government wants to pilot all-postal ballots in Yorkshire and the Humber in the European Parliament elections on June 10.

But there has been a huge row over proposals to trial all-postal voting in council and European elections.

Opponents fear people in multi-occupancy homes may not get their ballot papers and there may be "undue influence" from senior family members.

The independent Electoral Commission recommended the North-East and East Midlands should pilot all-postal voting. But the Government added Yorkshire and the Humber and the North-West.

This week, MPs voted by 269 to 166 - a 103 majority - to hold all-postal ballots in all four regions.

Updated: 10:32 Friday, March 12, 2004