NORTH ANDOVER, Mass. — A former Internal Revenue Service employee described by prosecutors as a "one man crime wave,'' was sentenced to five years in prison for the theft of more than $330,000 from The Home Depot stores in nine states.

Robert Dooley, 47, formerly of Salem, Mass., who pleaded guilty to the charges April 13, was sentenced Thursday in Boston by U.S. District Judge William Young.

Dooley, who had worked at the IRS Andover (Mass.) Service Center in 2001 and 2002, was convicted of devising a scheme to defraud The Home Depot stores on more than 470 occasions over a two-year period from 2003 to 2005.

He committed the scam in Massachusetts, Maine, New Hampshire, Connecticut, Vermont, Rhode Island, New York, Texas and Oklahoma, according to the U.S. attorney's office.

Prosecutors said Dooley would typically visit a store, put several items in a shopping cart and take them to the return desk.

Although The Home Depot allowed people to return items without receipts, clerks required customers to show photo identification when doing so.

Dooley used his IRS identification badge to persuade return clerks to give him store credit even though he had no receipt for the items stolen. He then sold or traded the store credit slips at a discounted rate, investigators said.

"By using his official IRS identification to advance his fraudulent scheme, Dooley abused his federal position and stained the reputation of many honest, hardworking employees," U.S. Attorney Michael Sullivan said in a statement.

During sentencing, prosecutors noted the full extent of the fraud will never be known because The Home Depot did not keep relevant store data for the first three years of Dooley's scheme.

Dooley was ordered to pay $335,665 restitution to The Home Depot, and will have three years of federal probation after his release from prison.