As postal voting started yesterday for the general election, the first postal ballot fraud investigation of the campaign opened.

A Conservative councillor in a Labour-held marginal seat is facing an inquiry into the number of people registered for postal votes at two addresses.

Jamshed Khan, a councillor in Bradford, faces questioning after it was discovered that 13 voters were registered at his six-bedroom home, all of whom have applied for postal votes.

A further 12, of whom half have applied for postal votes, are registered at a derelict house that he recently co-owned.

About 6.5 million ballot papers started arriving yesterday, allowing 15.5 per cent of the electorate to begin voting.

The deadline for postal vote applications is 5.00pm today.