A 53-year-old health care worker who lives in Chicopee, Massachusetts, has been named as the winner of more than US$750 million (NZ$1.05 billion) in a Powerball drawing, the largest prize for a single ticket-holder in the contest's history.
The woman, Mavis Wanczyk, appeared at an afternoon news conference on Thursday (US time) to claim her prize.
"I wanted to get this over and done with, and then everyone would leave me alone," Wanczyk, the mother of a 31-year-old daughter and a 26-year-old son, told reporters on Thursday.
She said she had worked for the past 32 years at a Springfield hospital, but added: "I've called them and told them I will not be coming back."
Powerball said on its website that the single ticket matched all six numbers drawn on Wednesday night: 6, 7, 16, 23, 26 and the Powerball of 4.
Wanczyk said she learned of her win when a colleague encouraged her to check her ticket as she left work on Wednesday.
"I said: 'I know it's never going to be me; it's just a pipe dream,"" Wanczyk said, adding that she was shocked to find "I am a winner."
The state lottery had originally said the winning ticket was sold in Watertown, a suburb of Boston, but corrected its announcement hours later.
"This was the result of a human error," Sweeney said. "Our internal systems, and I want to be clear about this, our internal systems always had the correct information."
Wanczyk will have a choice of receiving annual payments totalling $US758.7 million over 29 years, or a lump sum of more than $US440 million, before taxes.
Beyond retiring early, she did not say how she planned to spend her winnings.
The odds of a ticket having all six winning numbers are 292.2 million to 1, according to the Multi-State Lottery Association.