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The FBI began its investigation when threatening messages appeared on iFunny, an online forum, on Aug. 13, according to a complaint unsealed Monday. The user behind the posts, who went by the name “awarded,” was identified as Farhan Sheikh, authorities said.

When federal agents arrived at Sheikh’s Chicago residence last week with a search warrant, the 19-year-old suspected they were there because of a “joke” he had posted on iFunny, according to the complaint.

The allegedly humorous post? A threat to “slaughter and murder any doctor, patient, or visitor” at an abortion clinic about four miles from his home, the complaint said.

“I am done with my state and [their] bulls--- abortion laws and allowing [innocent] kids to be slaughtered for the so called ‘womans right’ bulls---,” Sheikh allegedly wrote in one of the posts. “Ive seen nothing but whores go out of the way to get an abortion, but no more. I will not tolerate this anymore. Im DONE. On August 23rd 2019, … I will proceed to slaughter and murder any doctor, patient, or visitor i see in the area and I will not back down. consider this a warning for anyone visiting …”

In another, he allegedly taunted, “come after me you degenerate government puppets, stop me if you can.”

On Monday, Sheikh, who was arrested last week, was charged with transmitting a threat in interstate commerce, which carries a maximum penalty of five years in prison, federal prosecutors in Illinois said in a news release. His arrest is the latest of its kind as law enforcement agencies continue to face heightened scrutiny over how they handle online threats of violence in the aftermath of recent back-to-back mass shootings in El Paso and Dayton, Ohio.

A lawyer for Sheikh could not be reached to comment early Tuesday.

After the initial threat targeting the abortion clinic, which was not named in court documents, Sheikh allegedly wrote a message to federal agents emphasizing that he was being serious.

“To all the fbi agents in this app, I am NOT a satirical account,” the message said. “I post what I mean and i WILL carry out what I post.”

In a subsequent post, Sheikh mentioned Justin Olsen, an 18-year-old from Ohio and fellow iFunny user, according to the complaint. Olsen, known online by the username “ArmyOfChrist,” was charged last week with threatening to assault a federal law enforcement officer after allegedly sharing posts that included statements such as, “Shoot every federal agent on sight.” Olsen, who told agents that his comments were “hyperbolic” and “only a joke,” also praised attacks on Planned Parenthood and mass shootings, The Washington Post’s Tim Elfrink reported. A raid of a home where Olsen lived turned up 10,000 rounds of ammunition, 15 rifles and shotguns and 10 semiautomatic pistols.

The post from Sheikh’s account, which had more than 1,100 subscribers, complained that Olsen had been arrested “for no reason except [suppressing] us and our freedoms,” authorities said.

“If killing babies is a right and practicing your freedom of speech isnt, then what kinda society is this?” Sheikh allegedly wrote in another comment. “I do not care anymore, may god forgive me for what I am going to do soon …”

Agents tracked Sheikh down through related social media accounts, arriving at his doorstep in Chicago on Friday, the complaint said. When asked at his home why he thought the FBI was there, Sheikh brought up the “joke” he had posted to iFunny. He later allegedly admitted that he had shared a post on the platform about shooting an abortion clinic and had been subscribed to Olsen’s “ArmyOfChrist” account. Sheikh also told the agents that the date and clinic mentioned in his posts were chosen at random, according to the complaint. Documents did not say whether any weapons were found at Sheikh’s residence.

Sheikh, clad in an orange jail uniform and flanked by U.S. marshals, made his initial appearance in court Monday, the Associated Press reported. A judge ordered that he remain in custody pending a detention hearing scheduled for Tuesday, according to the news release from the prosecutor’s office.

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