Twelve police forces across Britain send files to prosecutors as Tory battle bus investigation enters new phase

There are allegations that Tories broke spending limits at the 2015 general election

Two dozen Conservatives are understood to be under investigation over claims regards the 'battle bus' (Getty)

Twelve police forces around the country have sent files to the Crown Prosecution Service relating to general election expenses as an investigation into a Tory ‘battle bus’ scheme enters a new phase.

Officers have been looking into the Conservative Party’s battle bus campaign at the 2015 election to determine whether the party broke spending limits in target seats key to the party winning its narrow parliamentary majority.

Politicians campaigning to become MPs have to stick to strict local and national spending limits designed to help prevent the wealthy from having an unfair advantage at elections.

A spokesperson for the Crown Prosecution Service said it had received files from Avon & Somerset, Cumbria, Derbyshire, Devon & Cornwall, Gloucestershire, Greater Manchester, Lincolnshire, the Metropolitan, Northamptonshire, Nottinghamshire and West Yorkshire police forces.

A spokesperson for Staffordshire Police said they had also provided files to the CPS.

Two dozen Conservatives are understood to be under investigation over claims that they did not include battle bus spending in their local campaign returns. The Electoral Commission is also investigating the allegations in parallel to the police.

Allegations centre on whether spending on hotels for visiting activists and certain campaign material was incorrectly registered as national spending rather than locally – potentially taking advantage of a higher ceiling.

There have been suggestions that other parties may have failed to register similar spending in their local areas too.

In theory election results in individual seats could be declared invalid if laws are found to have been broken, though this is not an automatic process.

In recent days some Conservative MPs have hit out at party officials who they say have dodged blame for the fiasco at the expense of MPs’ reputation.

Additional reporting by PA