London police reopen probe into lockdown breaches at Conservative Party HQ

British police will reopen an investigation into Covid-19 lockdown breaches at a December 2020 event held in the headquarters of the governing Conservative Party following an assessment of new evidence.

However police said other referrals, made to them by the government following an examination of former prime minister Boris Johnson's diary, did not meet the criteria for further investigation.

The reopened investigation concerns a Christmas party organised by staff working on a mayoral election campaign.

No fines were issued when it was initially investigated, but a video recently aired by British media, which showed people dancing and partying at the event, has prompted officers to look again.

Police said their approach was only to retrospectively launch investigations when there was evidence of a serious and flagrant breach and other conditions were met.

The Conservative Party did not issue a fresh comment following the police announcement, and referred to a previous statement in which it said the gathering was unauthorised and that four staff had been disciplined as a result.

An additional investigation was opened into a Dec 8 2020 gathering in parliament, but police did not provide details about those in attendance.

Police also said they had assessed information provided by the Cabinet Office regarding potential breaches of the regulations between June 2020 and May 2021 at Johnson's then-Downing Street residence and office, and the prime ministerial country home, Chequers.

They had "concluded that they do not meet the retrospective criteria for opening an investigation", police said.