(Reuters) - A former Home Depot employee was sentenced to more than 30 years in federal prison for threatening to set off pipe bombs in some of the chain's suburban New York stores in an attempt to extort money from the retailer, his trial attorney said on Saturday.

Daniel Sheehan, 52, of Deer Park, N.Y., was convicted in 2013 of threatening to explode the bombs on the day after Thanksgiving Day the previous year, according to his trial attorney Leonard Lato.

So-called Black Friday is one of the busiest shopping days of the year.

Prosecutors said Sheehan tried to extort $2 million from The Home Depot by planting a pipe bomb in its Huntington, N.Y., store and threatening to plant three more in other stores, forcing them to close, if the money was not paid.

U.S. District Judge Denis Hurley in Central Islip, N.Y., sentenced Sheehan to 30 years and one month in prison on Friday, Lato said. The 30 years were mandatory under federal law for a conviction of using a destructive device in the commission of a felony, he said.

The judge said he would determine later how much money Sheehan owes Home Depot for security and other costs connected to the failed plot, according to Lato, whom Sheehan dismissed as his attorney following the verdict.

Prosecutors said Home Depot estimated spending about $1.5 million for security guards, bomb-sniffing dogs and other protection measures.

Sheehan earlier turned down a plea deal that carried a 12 year prison sentence, Lato said.

(Reporting by Ellen Wulfhorst; Editing by Stephen Powell)