A 99-year-old army veteran who has raised more than £8m for the NHS said the fundraising has been "completely out of this world".
Tom Moore aimed to raise £1,000 by completing 100 laps of his Bedfordshire garden by Thursday.
"Every penny that we get, they [the NHS] deserve every one of it," he said, as the total exceeded the £5m mark.
Meanwhile, a school girl has started a campaign for children to make cards for his 100th birthday on 30 April.
Reegan Davies, eight, from Port Talbot, Wales, has set a goal of making 1,500 virtual cards.
"You can post them on any social media with the hashtag #makeacardfortom." she said.
Mr Moore began raising funds to thank the "magnificent" NHS staff who helped him with treatment for cancer and a broken hip.
With the aid of a walking frame, he hoped to walk 100 laps of the 25-metre (82ft) loop in his garden in Marston Moretaine, in 10-lap chunks, before his 100th birthday.
More than 345,000 people from around the world have donated money to his fundraising page since it was set up last week.
At the government's daily press conference Health Secretary Matt Hancock said: "I want to pay a special tribute today to Captain Tom Moore.
"Captain Tom, you're an inspiration to us all, and we thank you."
As the amount exceeded £4m earlier, Mr Moore's daughter Hannah Ingram-Moore said they had thought raising £1,000 was a "real stretch" and the latest total was "just amazing".
'Humbled, floored and proud'
"It [has been] beyond our wildest expectations, no words can express our gratitude to the British public for getting behind Tom," she said.
"We are humbled, floored and proud.
"What the British public has done is given him his next purpose... I think he'll do this until everyone says 'stop, don't do this any more'."
He has said he will not stop and hopes to do another 100 laps.
Ellie Orton, chief executive of the charity NHS Charities Together, which will benefit from the funds, had said reaching £5m was "absolutely incredible".
She also wanted to "express our gratitude and our huge admiration for Captain Tom, for the NHS and for everybody who is donating".
BBC
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