SPRINGFIELD (AP) — A Boston police captain’s son accused of plotting an attack on a college campus to support the Islamic State group pleaded not guilty to terrorism charges Thursday.

Alexander Ciccolo, 24, was arrested last July in a plot to detonate homemade bombs similar to the pressure cooker bombs used in the deadly 2013 Boston Marathon attack. Boston police Capt. Robert Ciccolo alerted the FBI after his son said he wanted to join the Islamic State group.

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The younger Ciccolo was arrested after he allegedly received four guns from a person cooperating with the FBI.

Alexander Ciccolo (Photo from Napanee Beaver)

Alexander Ciccolo (Photo from Napanee Beaver)

He was charged then only with being a felon in possession of a firearm. But last week, he was indicted on one count each of attempting to provide material support to a foreign terrorist organization and attempting to use weapons of mass destruction.

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Ciccolo’s lawyer did not immediately return a call seeking comment Thursday.

Ciccolo has been held without bail since his arrest. During a detention hearing last July, a prosecutor said Ciccolo “came under the sway” of the Islamic State group, accepted its “call to action” and began making plans to kill Americans.

Prosecutors said Ciccolo focused on a plan to set off a pressure cooker bomb in the cafeteria of an unidentified university during lunchtime so he could kill as many people as possible.

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