Sunday’s papers are dominated by developments after police were called to a “row” at a flat shared by Boris Johnson and his partner Carrie Symonds.
The Tory leadership hopeful repeatedly refused to explain why officers had to visit the property, the Sunday Express reports.
Mr Johnson’s refusal to answer questions about the incident at a hustings event in Birmingham led senior Tories to raise concerns about his suitability for Number 10, The Observer reports.
Some allies of his rival, Jeremy Hunt, have claimed Mr Johnson is at risk of being blackmailed over his “colourful” private life, the Sunday Times reports.
Mr Johnson’s poll ratings took a hit as a result of the reports, according to surveys for the Mail on Sunday.
The Sunday Mirror leads with an account by the neighbour who rang the police after hearing the row in the early hours of Friday morning.
The neighbour’s wife had previously swore at the Conservative leadership candidate in the street and declared that “all Tories suck”, the Sunday Telegraph reports.
In other news, the Sunday People leads with a report on Karen Matthews.