11:44

Nicola Sturgeon has alleged that Theresa May called the snap election in part because she feared that numerous Tory MPs would be prosecuted for fraud over their election expenses, claiming the Tories may have “bought” the 2015 election.

Speaking at the Scottish TUC conference in Aviemore, Sturgeon said:

[This election was] called by the prime minister last week for one purpose and one purpose only - to strengthen the grip of the Tory party and crush dissent, and opposition. And to do so before possible criminal prosecutions for alleged expenses fraud at the last election catches up with her. And whatever else happens in this election we should not allow the Tory party to escape the accountability for any misdeamours that may have led to them buying the last general election.

The Crown Prosecution Service is considering police reports from 12 forces on the election claims of up to 20 Tory MPs, while the Conservatives have a working majority at Westminster of 17 seats. No one in the party has yet been charged with any offence. Some critics believe May in part wanted to secure a heftier majority to guard against her majority being chipped away by byelection defeats.

But this is difficult ground for Sturgeon: two former Scottish National party MPs have already had to sit as independents after police launched enquiries into their financial affairs.

Michelle Thomson in Edinburgh West and Natalie McGarry in Glasgow East, both of whom deny any wrongdoing, were barred from standing again by the SNP on Saturday.

McGarry has been charged with fraud and Thomson named in a police report to prosecutors into alleged mortgage frauds, but has not been charged. The Lib Dems believe they have a strong chance of winning back Edinburgh West as a result.