Aides for the show's runner-up called for an ambulance after Boyle suffered a reported "emotional breakdown" following her appearance on the TV show on Saturday.
Boyle, who was the pre-show favorite, was behaving strangely at a London hotel, which had been her base leading up to the big showdown, and medics were called, according to British newspaper The Sun.
A source tells the publication, "She'd been at the hotel for a few days, but since Saturday's final had been acting strangely, causing a bit of a stir. The staff were concerned, something wasn't right.
"When the paramedics and police arrived, she agreed to go voluntarily. She didn't make a fuss. The paramedics calmly took her out through the main lobby and into the waiting ambulance. It was all done very calmly. They didn't want to stress or upset her. She didn't look well -- she looked lost, not all there."
Boyle was taken to the Priory clinic in north London, where she is now recovering.
A spokesperson for Britain's Got Talent says, "Following Saturday's show, Susan is exhausted and emotionally drained. She has been seen by her private GP, who supports her decision to take a few days out for rest and recovery. We offer her our ongoing support and wish her a speedy recovery."
The Scot soared to international stardom after wowing judges and viewers with her amazing singing talents in her first audition on the program. She went on to become an Internet sensation, as more than 100 million fans watched her performance on image sharing website YouTube.
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