Dominic Cummings was called a “hypocrite” and told to resign by neighbours who heckled him on his return home.
Boris Johnson publicly backed his chief aide on Sunday, claiming Cummings “acted responsibly and with integrity” despite taking a 260-mile trip from London to Durham during the restrictions.
In one report, a witness alleges Cummings visited Barnard Castle, more than 25 miles from Durham, where he had been self-isolating.
Johnson called “some” of the claims “palpably false”.
But a scientist advising the government said Johnson had “trashed” the advice on lockdown by backing Cummings.
Cummings was heckled by a crowd gathered outside his north London home when he returned from Downing Street on Sunday evening.
Some of those gathered called him a "hypocrite" and shouted "resign".
One woman could be heard shouting: "My mum's terrified, my dad's had three shoulder operations… she won't even entertain me in her garden with a tent."
The woman, who filmed Cummings on her phone as she spoke, could then be heard telling him: "I'm a single parent. I've had no childcare since the beginning of this whole mess, not that I can afford to pay any childcare.”
Another shouted: "Would you recommend Barnard Castle for a day out?"
Cummings appeared not to respond to the heckling.
As he entered his home, shouts of "hypocrite", "resign" and "shame" could be heard from the group of onlookers.
Johnson defended Cummings on Sunday, saying his adviser’s lockdown trip was made on fatherly “instinct” to ensure care was available for his son.
Cummings travelled to County Durham in March to self-isolate with his family even though official guidelines warned against long-distance journeys, apparently because he feared that he and his wife would be left unable to care for their son if both were incapacitated by coronavirus symptoms.
Further reports also suggested the 48-year-old took a second trip to the North East in April, having already returned to London following his recovery from COVID-19.
An alleged eyewitness told the Daily Mirror he saw Cummings on 12 April and had reported him to Durham police.
Robin Lees, a retired teacher, says he spotted Cummings in Barnard Castle in County Durham on Easter Sunday.
It was reported that the number plate taken down by Lees was the same as one previously used by Cummings.
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