OFFICERS probing a series of lockdown-busting parties held on Downing Street have begun interviewing “key witnesses”, the Metropolitan Police have said.

In an update released on Monday afternoon the Met said that it had so far sent out more than 100 questionnaires “asking the recipients about their participation in alleged gatherings”.

Boris Johnson told Parliament that he had attended a bring your own booze party in the No 10 garden held during lockdown, but said he believed it to have been a work event.

Downing Street confirmed Johnson had been handed a questionnaire on February 11.

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The Met said in Monday’s statement: “Recipients are given seven days to respond. As a result of responses so far, further individuals have been identified and questionnaires sent to them. As the investigation continues, we may need to contact more people as further information comes to light.”

It went on: “The offences under consideration comprise a number of elements and the legislation itself changed between the event dates. We are progressing the investigation as quickly as possible.

“As yet, we have not made any referrals to the ACRO Criminal Records Office for the issuing of Fixed Penalty Notices. However, every questionnaire response is being assessed alongside all available evidence, and should this reach the evidential threshold, then referrals will be made.”