The latest American arrested for alleged ISIS sympathies and possessing firearms to presumably be used in a domestic attack is the 23-year-old son of a Boston police captain. His father, according to ABC News, was one of the first responders in the 2013 Boston Marathon bombing.

Arrests of American citizens with alleged intentions to carry out terrorist plots in the name of ISIS often take dramatic story arcs, but this one is laden with tragic irony.

According to the Justice Department's account, Alexander Ciccolo—who also goes by the name Ali Al Amriki—planned, like the Tsarnaev brothers in the 2013 attack, to set off a pressure-cooker bomb loaded with shrapnel in a crowded area. His father is Police Capt. Robert Ciccolo, who works at Boston police headquarters. According to a local CBS affiliate, the older Ciccolo turned his son into law enforcement.

"Ciccolo spoke with a cooperating witness in recorded conversations about his plans to commit acts of terrorism inspired by [ISIS], including setting off improvised explosive devices, such as pressure cookers filled with black powder, nails, ball bearings, and glass, in places where large numbers of people congregate, such as college cafeterias," a Justice Department press release states. "Prior to his arrest, agents observed Ciccolo purchase a pressure cooker similar to that used in the Boston Marathon bombings."

In a search of Ciccolo's apartment, law enforcement found "several partially constructed 'Molotov Cocktails,'" the press release continues. Ciccolo is charged with the illegal possession of firearms, including two pistols and two rifles.

In its investigation, the FBI was told by "a close acquaintance" of Ciccolo that he

had a long history of mental illness and in the last 18 months had become obsessed with Islam. The acquaintance also said that the defendant had recently stated that he believed that the "faith is under attack" and that he is "not afraid to die for the cause."

In a recording with a cooperating FBI witness, Ciccolo praised a lone-gunman terrorist attack in Tunisia that killed 38 people.

"Awesome, you know that, ah, that brother in Tunisia was impressive," the FBI recorded Ciccolo saying, according to the release. "He got like 38, 39 people "¦ one guy "¦ that is a huge accomplishment I think."

After Ciccolo was arrested, a DOJ detention memo reads, he stabbed a nurse during a routine medical screening.

"During his meeting with the nurse, the defendant grabbed a pen and forcefully stabbed the nurse in the head, leaving a bloody hole in the nurse's skin and causing the pen to break in half," the memo reads.

According to ABC News, FBI officials said Ciccolo's arrest is one of several in relation to threats of ISIS-inspired violence around the Fourth of July holiday.

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