The veteran known as "Captain Tom," who raised tens of millions of dollars for the British National Health Service, turned 100 Thursday, receiving a promotion from the Queen to the rank of "Colonel" and a special flyover to commemorate his achievements.

Earlier this month, Captain Tom Moore, who fought in WW2, captured the nation's hearts by launching a fundraising event by walking around his back garden to thank doctors who treated him for cancer. Moore originally aimed to raise £1,000 for charity, but his online campaign, set up just last week, has exploded -- he's received donations from hundreds of thousands of people.

Now, he's raised over $37 million for frontline National Health Service (NHS) workers in the U.K. battling the COVID-19 pandemic.

PHOTO: A handout picture released on April 30, 2020 shows Captain Tom Moore waving at a flypast by Battle of Britain Memorial planes to celebrate his 100th birthday in Marston Moretaine.
Emma Sohl/CAPTURE THE LIGHT/AFP via Getty
A handout picture released on April 30, 2020 shows Captain Tom Moore waving at a flypast by Battle of Britain Memorial planes to celebrate his 100th birthday in Marston Moretaine.

"100 years young today," Captain Tom posted on Twitter. "Looking forward to a day of celebration with the family. Today will be a good day!"

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Spitfire planes from the Royal Air Force performed a spectacular flyover over the veteran's house to mark the occasion.

"This event has been amazing for us, helping us get through the lockdown," Benjie Ingram-Moore, Captain Tom's grandson told ABC News earlier this month. "My parents have 20,000 emails to reply to -- we haven't been off our laptops!"

The U.K. Prime Minister Boris Johnson issued a special statement to thank Captain Tom and wish him a happy birthday.

"Your heroic efforts have lifted the spirits of the entire nation," Johnson said. "You've created a channel to enable millions to say a heart-felt thank you to the remarkable men and women in our NHS."

He also received a birthday message from the Royal Opera House.

Captain Tom's promotion to Honorary Colonel was approved by Queen Elizabeth II and he received a personal letter from Her Majesty, which the veteran described as "rather special."

"I'm delighted that Capt Tom Moore has agreed to be Honorary Colonel of AFC Harrogate where our youngest soldiers are trained & educated," the British Army's Chief of Staff said. "He is an inspiration & role-model to generations and this deserved promotion is applauded across all ranks. Happy 100th Birthday Colonel Tom."

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