Dominic Cummings has been asked to hand over mobile phone and vehicle tracking data to disprove claims that he made a second lockdown trip to Durham at the height of the pandemic. The request was made by Nazir Afzal, the former chief prosecutor for north-west England, who is leading a campaign for a full investigation into Cummings’ movements during the lockdown. It was prompted by allegations from Dave and Clare Edwards and two others, who told the Guardian and the Daily Mirror that they had seen someone whom they believed to be Cummings in woods south of Durham on 19 April, days after he returned to London following his now notorious 17-day trip to the north-east. The prime minister’s chief aide has denied making a second visit and says he has phone data to prove he was in London on 19 April. Boris Johnson says he has seen this evidence, but Downing Street has refused to make it available and regards the matter as closed. In separate letters to Cummings and his wife, Mary Wakefield, however, lawyers for Afzal say there is a public interest in settling the matter by verifying the true extent of their lockdown movements including over the weekend of 17-19 April. Explaining the move, Afzal said: “All we ask, on behalf of the law-abiding public, is that Mr Cummings, who has regularly spoken about the importance of data, provide the data that will evidence his whereabouts and prove he was telling the whole truth in the Downing Street garden. “We have written to Ms Wakefield too because she has yet to give an account of her whereabouts, which has become increasingly relevant as witnesses give their accounts. The public deserve the truth, nothing else.” The letters request location data from the couple’s mobile phones for their first trip to the north-east and for the disputed weekend. They also ask for tracking data from the two Land Rover Discovery vehicles the family were seen using in April and May. The models Cummings used record all the vehicles’ movements and share the data with the manufacturer. The letters also ask for the couple’s authorisation for police to check automatic number plate recognition records for the lockdown movements of the vehicles. Their authorisation is also requested for Land Rover and Google to release location data. At his press conference in the Downing Street rose garden in May, Cummings said it was untrue to claim that he had returned to Durham on 19 April. He said: “Photos and data on my phone prove this to be false, and local CCTV, if it exists, would also prove that I’m telling the truth that I was in London on that day. I was not in Durham.” The letter to Cummings from Afzal’s lawyers reads: “Having highlighted the importance of such evidence to the nation, you will no doubt agree that it is important that you ensure its provision, in light of the continuing controversy surrounding these matters. “Because you expressly made reference to and relied upon phone and other camera-recorded data that you said would corroborate your account and would show that the contradictory witness accounts were ‘false’, any unwillingness now to produce that data would be highly significant.” Durham police found that Cummings probably breached health protection rules by travelling to Barnard Castle on 12 April, but made no finding on his decision to leave London because the three-day investigation was confined to County Durham. Afzal, whose older brother died of Covid-19 on 8 April, and senior Labour figures have called on the Metropolitan police to investigate all Cumming’s alleged lockdown breaches. Afzal’s letters also cite research that found a clear and lasting dip in public confidence in the government’s handling of the pandemic following the exposure of Cummings’ movements.