An expert involved in the fight against coronavirus has described conspiracy theories linking 5G technology to the pandemic as “utter rubbish” after videos showing masts on fire were posted on social media.

Condemning the theories as “the worst kind of fake news” at a Downing Street press conference, national medical director of NHS England Professor Steve Powis said: “I’m absolutely outraged, absolutely disgusted, that people would be taking action against the very infrastructure that we need to respond to this health emergency. It is absolute and utter rubbish.”

Cabinet Secretary Michael Gove added: “That’s just nonsense, dangerous nonsense as well.”

Mobile UK, the trade body which represents network providers, said key workers had been abused and infrastructure threatened as a result of the claims.

On Thursday evening, West Midlands Fire Service said eight firefighters attended an incident involving a 70ft tower on a telecommunications site in the Sparkhill area of Birmingham, although the cause of the fire was not determined.

Fire crews were called to a blaze at a phone mast in Aintree, Merseyside, on Friday night but a spokeswoman for Merseyside Fire and Rescue Service said there were “no signs of foul play” so an investigation into its cause was not launched.

The mast had been featured in a video shared on social media the previous weekend by someone who claimed to be measuring radiation from it.

Professor Adam Finn, professor of paediatrics at the University of Bristol, said: “The internet connections these networks give us are one of the most important tools we are using to co-ordinate our response to the epidemic and efforts to do research to overcome it.”

MORE: Eight more coronavirus deaths in Norfolk as UK death toll jumps by 708Prof Brendan Wren, professor of microbial pathogenesis, at the London School of Hygiene & Tropical Medicine, said a connection between the phone masts and the virus would be “both a physical and biological impossibility”.

At the same press conference Mr Gove also warned that young people may not be taking social distancing measures seriously despite strict instructions to stay at home.

People were spotted sunbathing in some parts of London and the north east today on the warmest weekend of the last six months - which is the second the UK has spent in lockdown due to Covid-19.

Mr Gove said there was “evidence to suggest” compliance varies across different demographics of the population.

He explained: “There has been evidence that for some young people, there has been a lower level of compliance. That is why it is important that we reach them appropriately - it may be that some of the messages and some of the channels we have used have not reached some segments of the population.

“It may be that young people feel that they are less likely to be affected and less likely to be infected.”

Mr Gove urged people to consider the current pressure on the NHS, and to ask themselves: “How am I helping in this shared national effort?”

He added: “I know that lockdown is challenging, I know it’s very difficult, particularly for families with children.

“But people must at every stage respect these guidelines because that is the only way of making sure we restrict the spread of the disease.”