By GUY DAVIES, ABC News

(LONDON) — Capt. Sir Thomas Moore, the World War II veteran who raised tens of millions for frontline health workers during the coronavirus pandemic, has died at the age of 100.

The veteran, affectionately known as “Captain Tom,” tested positive for COVID-19 last week, and was hospitalized on Sunday due to complications with his breathing. Moore had received treatment for pneumonia over the past few weeks, his family said. His death was confirmed on social media accounts run by his family.

pic.twitter.com/4QHUcwrHiH

— Captain Tom Moore (@captaintommoore) February 2, 2021

Moore rose to international prominence in April 2020 when he began fundraising for the health workers who had treated him for cancer by walking around his garden in Buckinghamshire, England, in the weeks leading up to his 100th birthday.

Initially, Moore had set out to raise just £1,000 ($1,370), but his efforts captured the hearts of millions in the U.K. and abroad in lockdown. Eventually, he is estimated to have raised £37 million ($50.7 million) for frontline health workers.

In July, he was knighted by Queen Elizabeth II. Reacting to that news, Moore displayed his trademark humility and sense of humor, saying: “I’m still Tom Moore. I mean, it’s nice. It’s nice, I think Sir Thomas sounds very nice, but inside I haven’t changed. Nothing’s changed inside.”

During New Years Eve celebrations in London, Moore was honored with his own personalized fireworks display, complete with his trademark walking aid and military badges, and was hailed by Mayor of London Sadiq Khan as a “true national hero.”

A true national hero. When we all needed a lift during the first lockdown @CaptainTomMoore was there to show us that anything is possible.

Thank you, Captain Sir Tom. #LondonTogether pic.twitter.com/E3F6HfO9FE

— Mayor of London (gov.uk/coronavirus) (@MayorofLondon) January 1, 2021

Moore’s fundraising exploits made headlines across the globe, and inspired a fellow Russian veteran, 97-year-old Ziniaida Korneva, to take up similar efforts.

In December, along with his family, Moore took a trip to Barbados, which was part of an international travel corridor with the U.K.

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