FBI Investigating 1,000 ISIS-Related Threats in All 50 States

(Photo: REUTERS/Kristina Barker)An American flag is seen along Wyoming Highway 59 near a residential housing development south of Gillette, Wyoming, U.S. May 31, 2016.

Days after Charlotte-area ISIS sympathizer Justin Sullivan was sentenced to life for planning mass murder in support of the Islamic State terror group, a North Carolina-based terrorism expert says the FBI is investigating about 1,000 ISIS-related threats in all 50 states.

U.S. Attorney Jill Rose of Charlotte has confirmed that suspected ISIS sympathizers are being investigated in North Carolina while not disclosing the number, a "domestic-terrorism expert" told The Charlotte Observer that the state probes are among some 1,000 active FBI investigations.

After Sullivan's conviction this week, Keri Farley, the FBI's assistant special agent in charge of North Carolina, was quoted as saying that while Sullivan's arrest saved lives, "homegrown violent extremists" are becoming more difficult to deal with.

"Identifying a terrorist before an attack happens is one of the most difficult challenges we face," she said at a press conference. "It's harder than finding a needle in a haystack; it's like finding a needle in a stack of needles. But that's exactly what happened in this case."

According to the Program on Extremism at George Washington University, 126 people, mostly young men, have been arrested in the country over the last three years for ISIS-related acts or conspiracies.

While about 45 percent were arrested while trying to join ISIS fighters abroad, around 30 percent have been accused of being involved in plots to carry out attacks on U.S. soil, the program says, adding that 58 percent were charged in an operation involving an informant and/or an undercover agent.

The program has also found that the average age of those charged is 27, and their activities were located in 26 states and the District of Columbia.

During the trial, U.S. District Judge Martin Reidinger said the massacre planned by 21-year-old Sullivan was similar to the 2016 attack in Orlando, Florida, where one gunman killed as many as 49 people. Sullivan was also planning to unveil the "Islamic State of North America."

"Sullivan is a convicted terrorist who plotted with now-deceased Syria-based terrorist Junaid Hussain to execute acts of mass violence in the United States in the name of ISIS," Acting Assistant Attorney General for National Security Dana Boente said in a statement earlier. "Counter terrorism remains our highest priority and we will continue to identify and hold accountable those who seek to commit acts of terrorism within our borders."

Court records show Sullivan expressed support for ISIS inside his own home and destroyed religious objects that belonged to his parents. It was ultimately his father, Rich, who contacted the authorities about his radicalization in 2015.

Last month, prominent ex-Muslim writers who are now Christians urged the West to spurn the idea that Islamic terror attacks are the "new normal," a phrase they say emboldens the terrorists to continue rampaging.