The number of children diagnosed with a rare coronavirus-related syndrome in the UK is between 20-30 over the past few weeks, Mirror.co.uk can reveal.
The mysterious new coronavirus-related illness hit the headlines yesterday after doctors across the UK were sent an urgent alert about it.
The illness, which is yet to be named, is thought to affect children, and may be related to COVID-19.
Worryingly, the illness can cause several unpleasant symptoms, including abdominal pain and cardiac inflammation.
An NHS source told Mirror.co.uk that the number affected by the mystery illness was "in the ball park of 20-30 children".
This is the same figure This Morning's Dr Ranj Singh revealed while speaking about the mystery illness on today's show.

He told hosts Phillip Schofield and Holly Willoughby : "We're definitely seeing it in school age children in this country and we don’t know exactly how many children are affected in the UK but we’re guessing probably between 20-30 have been affected over the last few weeks.
"Not all of them have been serious. We have seen some reports from other countries as well. For instance, my colleagues in Spain have started to report they have seen some cases of this too."

The alert to doctors explained that there's been a rapid increase the number of cases in the last three weeks.
It said: “[In the] last three weeks, there has been an apparent rise in the number of children of all ages presenting with a multisystem inflammatory state requiring intensive care across London and also in other regions of the UK.
“There is a growing concern that a [covid-19] related inflammatory syndrome is emerging in children in the UK, or that there may be another, as yet unidentified, infectious pathogen associated with these cases.”
Home Office Minister Victoria Atkins has urged parents to be ‘vigilant’ over the new coronavirus-related condition.
Speaking to Sky News, Ms Atkins said: “The Chief Medical Office and NHS England are looking at this very carefully, but it demonstrates just how fast moving this virus is, and how precedented it is in its effects.
“The advice to parents, is if they’re worried about the recovery of their children then they must please seek medical help to ensure they’re being looked after by the NHS.”
Ms Atkins added that while the new illness is extremely rare, parents need to be vigilant.
She said: “I’m a Mum of a young child, we must all be watching our children very carefully through this virus, and if we’re worried about the recovery of our children, then we must seek medical help.”

Health Secretary Matt Hancock has revealed that we still don’t know if the new illness is fatal or not.
Speaking to LBC this morning, he said: “There are some children who have died [after testing positive for Covid-19] who didn’t have underlying health conditions that I know of.”
He added: “It’s a new disease that we think may be caused by coronavirus and the Covid-19 virus, we’re not 100% sure because some of the people who got it haven’t tested positive, so we’re doing a lot of research now.
“It is something we’re worried about but I would also stress it is rare.”