DETROIT (WWJ/AP) – A 29-year-old Detroit man convicted of using a gun to rob phone stores has been given an extraordinary sentence of 116 years in federal prison.

Timothy Carpenter’s sentence is long because he was convicted of crimes that carry mandatory, consecutive sentences under federal law. He was accused of robbing phone stores in Detroit, Highland Park, Eastpointe, and Warren, Ohio between December 13, 2010, and December 1, 2012.

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“Armed robberies at neighborhood stores make citizens fearful to carry out their daily business in our community,” said U.S. Attorney Barbara McQuade, adding that the sentence sends a “powerful message” that using guns to commit crimes won’t be tolerated.

Carpenter was convicted following two-week jury trial in December, and sentenced Wednesday by Detroit federal Judge Sean Cox.

Ahead of the hearing, defense attorney Harold Gurewitz said the punishment would be “grossly disproportionate” to the crimes and unconstitutional. He says guns were used but never fired.

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The case was investigated by the FBI.

“Aggressively pursuing violent offenders, particularly those associated with organized criminal groups, is among the highest priorities of the FBI,” said Paul Abbate, Special Agent in Charge of the FBI Detroit Field Office, in a released.

“Today’s sentence, along with others seen recently, sends a strong message to violent perpetrators whose actions wreak havoc upon our community—the FBI, our local, state and federal partners, and the U.S. Attorney’s Office will work tirelessly to combat violent crime and bring justice to bear on these offenders.”

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