Samuel Rahamin Topaz of Fort Lee, New Jersey is seen playing guitar on a Facebook video. He has now been charged with three other men to provide material support to the Islamic State terror group. (Credit: CBS2)

NEWARK, N.J. (CBSNewYork/AP) — A New Jersey man has been charged with conspiring with three other men to provide material support to the Islamic State terror group.

Samuel Rahamin Topaz, of Fort Lee, was arrested Wednesday and is charged with conspiring with others in New Jersey and New York to provide services and personnel to ISIS.

According to prosecutors, the 21-year-old was arrested at his home and made an initial court appearance in front of a federal judge in Newark Thursday. He is being held without bail.

Prosecutors alleged one of Topaz’s co-conspirators was a Munther Omar Saleh, 20, who was arrested in Queens this week. Another alleged co-conspirator traveled oversees to join ISIS in May, prosecutors said.

The third co-conspirator wasn’t identified but was said to be a New Jersey resident.

As CBS2’s Jessica Schneider reported, the suspect shared ominous posts on social media.

Topaz posted selfies on Facebook wearing the head and face coverings similar to those worn by jihadist fighters.

One of his friends alerted the FBI to his troubling behavior.

Topaz lives in a Fort Lee apartment building with his mother and younger brother.

He used to sing and was in a band — and was seen playing guitar in a Facebook video. But in the past few months the feds said he withdrew from his friends and began associating with men that the FBI had been monitoring — including Saleh, 20, the student from Queens arrested Saturday near the Whitestone Bridge.

Saleh is accused of planning an attack on New York City landmarks on behalf of ISIS.

A complaint alleges months of correspondence between Topaz and Saleh, and two other men. One of the men left the U.S. to fly to the Middle East last month.

The men allegedly made plans to join ISIS but ran into financial issues.

“I’m not sure how much longer I can take not being in the Dawla. Honestly, everything is so accesible and unchangeable and excessive in American that I feel any much longer I’m here I might just start fasting to get much closer to God,” Topaz said in a text to Saleh on May 4.

Agents executed a search warrant and arrested Topaz on Wednesday.

Debra Weinberg saw Topaz being led out of his home in hadcuffs.

“I think it can happen here because we’re very close to Manhattan and it makes me nervous, but you have to go on with your life,” she said.

The feds said that after his arrest Topaz admitted to sympathizing with ISIS and planned to travel overseas.

Another man, Fareed Mumuni of Staten Island, was also arrested Wednesday morning after allegedly attacking an FBI agent with the Joint Terrorism Task Force with a knife during a search of his home.

Investigators said Mumuni “repeatedly attempted to plunge the kitchen knife into the torso of an FBI Special Agent,” CBS2’s Jessica Schneider previously reported.

None of the stabs penetrated the agent’s body armor, and he suffered only minor injuries, according to the criminal complaint.

Authorities said Mumuni and Saleh were plotting to explode a pressure cooker bomb in the city, CBS2 reported.

If convicted, Topaz faces a maximum of 15 years in prison and a $250,000 fine.

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