UPDATE: Suspect appears in court

A 19-year-old Harrisburg man arrested in an FBI raid Thursday is accused of using the internet to spread propaganda of the ISIS terrorist group, advocate violence within the U.S. and aid terrorists in traveling to the Islamic State.

All those accusations are made against Jalil Ibn Ameer Aziz in U.S. Middle District Court filings by a special agent with the FBI's Joint Terrorism Task Force, which swept down on Azziz's home at 1733 Fulton Street around 2 p.m.

The unnamed agent said investigators also found a tactical backpack, military-grade ammunition, high-capacity gun magazines and a "modified kitchen knife" in the rented home Aziz shares with his parents.

U.S. Attorney Peter Smith issued a statement advising the public not to "give in to fear or unreasonable anger" or to target Muslims for violence in reaction to the announcement of charges in the AZIZ case.

"Such actions only serve the interests of the terrorists and violent extremists," Smith said.

Aziz was arraigned in the federal courthouse in Harrisburg Thursday afternoon. Lori Ulrich, one of the federal public defenders assigned to represent Aziz, declined to comment on the case Thursday evening.

A search warrant application the agent filed, and which was unsealed by a federal judge just after Aziz's apprehension, states that he has used 57 Twitter handles to push propaganda from ISIS, which controls part of Syria and Iraq and which is blamed for recent terrorist attacks in the U.S., Paris, France, and other spots around the globe. The group is also known by the acronym ISIL, which is cited in the search warrant.

The agent claims Aziz, a U.S. citizen who is believed to be jobless, abetted ISIS recruiting under false identities that included "Colonel Shami." He has also promoted videos of beheadings committed by the terrorists and chatted about buying women enslaved by ISIL, the agent wrote.

"Aziz commonly uses his Twitter accounts to spread pro-ISIL propaganda, including news from ISIL sources, as well as execution photos and videos," according to the search warrant. He also has used Twitter to encourage people to contribute money to the terrorists, "express his desire to make pilgrimage to ISIL-controlled territory, provide advice on how to travel inconspicuously, and facilitate others' travel to fight for ISIL," the agent claims.

The agent said Aziz used Twitter to pledge allegiance to ISIL and its leader, Sheikh Abu Bakr Al Baghdadi, in June 2014.

He kept creating new accounts whenever Twitter would shut down his accounts for terrorist activity, the agent said.

"In this instance, Aziz operated quietly on behalf of the Islamic State and facilitated others looking to do the same, said William F. Sweeney Jr., Special Agent in Charge of the FBI's Philadelphia Division.

The agent who filed the search warrant cited Twitter messages in which Aziz allegedly advocated the killing of "all kufar," which translates as infidels, or non-Muslims. In January, he said Aziz tweeted the message "Know O Obama that we are coming to America and know that we will sever your head in the White House." The same post showed a masked ISIL militant beheading an unknown soldier.

Last April, he tweeted, "Perform your Islamic duty. Support the jihad with your wealth," the agent wrote. A month earlier, the agent said, Aziz advised his Twitter followers that "Pennsylvania have very light gun laws its very easy to arm yourself."

In July, Aziz chatted with other ISIS advocates about buying women from the Yazidi ethnic minority held captive by ISIS to use as slaves, the agent stated. ISIS is known for forcing captive women into marriages, or simply using them as sex slaves for its fighters.

Other tweets by Aziz, the agent wrote, advocated attacks of members of the U.S. military, expressed his desire to travel to the ISIS "caliphate."

He praised a hacker who revealed the addresses of 100 American military personnel in March, according to court documents.

The agent wrote that in May Aziz provided information, including maps and direction to an unnamed co-conspirator who wanted to travel to Syria to fight for ISIS, and told the man how to download a messaging app to send coded messages. He also advised the man to wipe his computer clean of all ISIS material and to avoid wearing "Muslim clothes," the agent said. He said Aziz chatted with t least two other potential ISIS recruits as well.

A search by law enforcement on Nov. 27 turned up the backpack, ammo, gun clips and modified knife in Aziz's closet, the agent said. He said officers also found a thumb drive, a tin filled with over-the-counter medications and a head wrap commonly worn by ISIS members to hide their faces.

The search warrant specifically targeted Aziz's computers, which the FBI intended to subject to rapid examination for potential terror leads.

The FBI has had Aziz under surveillance for a period not outlined in the court filings. That surveillance "has observed that Aziz rarely leaves the residence." the agent wrote. "When he does leave the residence, it is usually not for an extended period of time."

It is evident that investigators were alerted to target Aziz by his online activity. Besides weapons and computer gear, the search warrant sought the seizure of any "manifest, writings, maps or other documents that show the planning or preparation of violence."

Prosecutor Smith called the arrest of Aziz "a testament to the perseverance and dedication of those who stand watch over our nation and a clear message that those who support terrorism - will face justice."

"We must be alert, responsible and smart, as demonstrated by the actions of the FBI and other agencies in this case," he added

Smith did more than simply speak against retaliation against Muslims following Aziz's arrest. Such crimes against Muslims will be prosecuted as hate crimes, he vowed.

Sweeney, the FBI special agent in charge urged residents to report any suspicious persons or incidents to law enforcement.

A Fulton Street neighbor, Lynn Shauf, said she witnessed the raid by heavily armed FBI agents and saw a man being taken away in handcuffs. FBI vehicles remained on the cordoned-off street for hours.

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