The family of Mavis Wanczyk, who has won the largest ever US Powerball prize, was hit by tragedy previous year when her ex-husband was killed.
"The first thing I want to do is just sit back and relax", Mavis L. Wanczyk told reporters at a news conference.
Officers have also talked to neighbors and told them to call police if they see something out of the ordinary, he said.
Lottery officials say she chose to take a lump sum payment of $480 million, or $336 million after taxes.
She said she had already quit her job, a clerical one that she had done for 32 years in the nursing department of Mercy Medical Centre. "It's just a pipe dream that I've always had".
Ms Wanczyk has two children-a son and a daughter.
In Michigan, one ticket sold matched four white balls and the Powerball to win $50,000 in the drawing.
The press conference followed a morning of confusion after the Massachusetts State Lottery initially said overnight the winning ticket was sold at a Watertown store, only to issue a correction early Thursday that it was purchased at the Pride Station & Store at 27 Montgomery Street in Chicopee.
The lucky numbers from Wednesday night's drawing are 6, 7, 16, 23 and 26, and the Powerball number is 4.
The 20-year-old store clerk at the Pride Station & Store in Chicopee sold the ticket to the 53-year-old hospital worker who came up with the winning combination of numbers.
While he doesn't yet know who his lucky customer is, he said he was informed that the jackpot-winning ticket was sold Wednesday around 2:30 p.m.to a woman. "We apologize for the confusion this created and remain thrilled that a jackpot winning ticket and two $1 million winning tickets were sold here in MA". Around 10 million other lottery tickets won the prizes of more than $135 million.
Tom Rietz, a professor at the University of Iowa who researches probabilities, says it's hard for people to fathom what odds of one in 292.2 million mean.
A winning ticket matches five numbers drawn between 1 and 69 while the "Powerball" number is drawn from 1 to 26.
Amid all the talk about sudden wealth, it's easy to forget that the goal of Powerball is to raise money for government programs in the 44 states where the game is played, as well as Washington, D.C., Puerto Rico and the U.S. Virgin Islands.