Transcript for Syrian refugee charged with targeting US church

Now to a terror plot targeting a Pittsburgh church thwarted by the FBI. A Syrian refugee is under arrest and Pierre Thomas is in Washington with all the details. Good morning, per. Reporter: Good morning. The FBI lays out a chilling case accusing a young Syrian man of plotting to attack a house of worship in the name of ISIS. The target this small Pittsburgh church and the alleged plot to detonate an explosive device strong enough to destroy the church and a blast so powerful it would likely kill many people in the residential area. It's devastating but that's the time we live in. Reporter: The FBI descending on the home of mustafa mousab alowemer, a 21-year-old refugee from Syria who came to the U.S. In 2016. It was actually like really scary. If this would actually go through and happen, that would have been more detrimental than I can emergency. Reporter: According to the FBI alowemer did surveillance on the church after considering many targets in the Pittsburgh area. It called for an attack in the upcoming month of July and said alowemer purchased bombmaking components including batteries and cam cals. The plan was to detonate them remotely. According to a transcript of him speaking to an FBI undercover operative, he said, when we have a goal we can leave a book bag or something and like we blow it up from someplace. I'm looking for a way to leave. I don't want to get caught. The FBI identified the suspect in part because he was allegedly obtaining large amounts of ISIS propaganda. The justice department claims at one point alowemer reached out to what he thought was a ISIS radical based overseas. It turns out it was a covert employee of the FBI posing an as ISIS sympathizer online, Michael. Good thing he was caught. And the FBI have been on high alert for these plots. Reporter: This is the same community that saw the tree of life synagogue massacre last October and I was eeptsly at an FBI briefing where a senior FBI official warned that the agency is experiencing a higher tempo of terrorism cases than they've seen in a long typing. Roughly 5,000 open cases internationally and here at home, this includes 1,000 ISIS cases. 850 domestic terrorism cases, some involving white supremacists and 1,000 so-called homegrown ex-treatmentists. Thanks. That dangerous weather on the move, 52 million Americans

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