NEW YORK (CBSNewYork/AP) — Israeli police arrested a 19-year-old Israeli Jewish man as the primary suspect in a string of bomb threats targeting Jewish community centers and other institutions in the U.S., marking a potential breakthrough in a case that stoked fears across America.

Police spokesman Micky Rosenfeld described the suspect as a hacker. Israeli media identified him as an American-Israeli dual citizen and said he had been found unfit for compulsory service in the Israeli military.

“He’s the guy who was behind the JCC threats,” Rosenfeld said, referring to the dozens of anonymous threats phoned in to Jewish community centers in the U.S. over the past two months.

“Israeli National Police have arrested a suspect threatening to have bombs in schools and other facilities,” a police official said.

Israel’s Channel 10 TV showed footage of the suspect appearing in court in the central Israeli city of Rishon Letzion. He wore tan pants and a blue sweater that he used to cover his face as he walked past reporters. The channel said the young man had lived in the U.S. for a period of time and had been home-schooled. It showed images of a large antenna outside his house and said his father was also arrested.

At the courthouse, the suspect’s lawyer, Galit Bash, told reporters that her client had a “very serious medical condition” that had kept him out of compulsory military service and might have affected his behavior.

He “didn’t serve in the army, didn’t go to high school, didn’t go to elementary school,” she said. “So that’s why the medical condition can actually affect the investigation.” Channel 10 described the condition as a brain tumor.

A judge in Israel has ordered a medical evaluation before the man is charged.

Israeli police said the suspect made dozens of calls claiming to have placed bombs in public places and private companies, causing panic and “significant economic damage,” and disrupting public order, including by the hurried evacuations of a number of public venues around the world. The man is suspected of placing threatening phone calls to Australia, New Zealand and also within Israel.

Rosenfeld said the man called Delta Airlines in February 2015 and made a false threat about explosives aboard a flight from John F. Kennedy Airport. The threat allegedly led to an emergency landing.

Rosenfeld said the man, from the south of Israel, used advanced technologies to mask the origin of his calls. He said police searched his house Thursday morning and discovered antennas and satellite equipment.

“He didn’t use regular phone lines. He used different computer systems so he couldn’t be backtracked,” Rosenfeld said.

Former FBI Agent Manny Gomez commends the intelligence community for tackling the daunting task of tracking cyber criminals.

“Online threats are a big problem now,” Gomez told CBS2. “U.S. intelligence and U.S. law enforcement has to discern throughout the hundreds of credible threats that come in on a weekly and monthly basis.”

After an intensive investigation in cooperation with FBI representatives who arrived in Israel, as well as other police organizations from various countries, technology was used to track down the suspect who had made the threats around the world, Rosenfeld said.

The FBI released a statement confirming the arrest and commending the work of the Israeli National Police, but did not go into details about the investigation.

“Investigating hate crimes is a top priority for the FBI and we will continue to work to make sure all races and religions feel safe in their communities and in their places of worship,” the statement read. “At this time, we cannot provide additional information on the investigation.”

Attorney General Jeff Sessions commended investigators in the U.S. and Israel for their joint effort in tracing the suspect’s digital trail.

“Today’s arrest in Israel is the culmination of a large-scale investigation spanning multiple continents for hate crimes against Jewish communities across our country,” Sessions said. “The Department of Justice is committed to protecting the civil rights of all Americans, and we will not tolerate the targeting of any community in this country on the basis of their religious beliefs. I commend the FBI and Israeli National Police for their outstanding work on this case.”

The suspect’s motives remain unclear.

“Was he acting alone? Was he acting with others? What was his intent? Why did he do this? And was the threat real — was he going to act on it,” Gomez said of the ongoing investigation. “It could be an attention-seeking thing, it wouldn’t surprise me that at the end of the day we find out that this is a young man with certain issues and that he was doing this to get attention.”

“I think it’s ironic that he’s Jewish. One would’ve thought that somebody that’s posing a threat to the Jewish community would be an anti-Semite or somebody who has something against the Jewish community,” he added.

It’s still unclear whether the man will be sent back to the U.S. to face charges.

According to the Anti-Defamation League, there have been more than 150 threats against Jewish institutions in 37 states and two Canadian provinces since Jan. 9. The threats were accompanied by acts of vandalism on several Jewish cemeteries.

The ADL said it was “relieved” that there’s been an arrest in the case, but urged the Jewish community to remain vigilant.

“Identifying the suspect who allegedly did the majority of these bomb threats I think can bring some relief to the institutions that experienced these. So in that sense, we’re relieved,” ADL regional director for New York Evan Bernstein said. “We’re happy this is taking place, we’re happy there’s been some resolution here. Now we can’t let our eyes be taken off the ball about some of the other big issues facing the state of New York.”

“Personally, it’s saddening. As a Jew and a as Zionist, to hear that the person is an Israeli Jew is very tough,” he added.

“While the details of this crime remain unclear, the impact of this individual’s actions is crystal clear: These were acts of anti-Semitism. These threats targeted Jewish institutions, were calculated to sow fear and anxiety, and put the entire Jewish community on high alert,” ADL CEO Jonathan Greenblatt said in a statement.

“Even though it appears that the main culprit behind the majority of these attacks has allegedly been identified, anti-Semitism in the U.S. remains a very serious concern. No arrests have been made in three cemetery desecrations or a series of other anti-Semitic incidents involving swastika graffiti and hate fliers. JCCs and other institutions should not relax security measures or become less vigilant,” he added.

Relieved and thankful to law enforcement for arresting suspect in #bombthreats to Jewish institutions. Stay tuned for more info. — ADL (@ADL_National) March 23, 2017

Doron Krakow, CEO of the JCC Association of North America, said the organization was “troubled to learn” that the suspect is Jewish.

“We are gratified by the progress in this investigation, and applaud the commitment and leadership of the FBI and other federal agencies, Israeli law enforcement, and local law enforcement across the United States and Canada,” Krakow said. “Throughout this long running period of concern and disruption that we are hopeful has come to an end, JCCs have had the opportunity to review and assess our security protocols and procedures, and we are confident that JCCs are safer today than ever before.”

Jordan Shenker, head of the Kaplen JCC on the Palisades in Tenafly, said he is cautiously optimistic that the man arrested in Israel on Thursday acted alone and that the threats will be over. Shenker, whose center received three phone threats since January, said the arrest has led to a feeling of being able to exhale, but that the center has always prioritized security and will continue to.

“I think there’s a sense of relief that somebody has been arrested and identified as centrally responsible for a large number of these calls,” Shenker told WCBS 880’s Marla Diamond. “Certainly very thankful to the FBI and the international intelligence community for the effort, energy and priority they put on resources to identify who has been responsible for these acts of hatred and intolerance.”

New York Gov. Andrew Cuomo said he hopes the arrest “brings comfort to those affected by his despicable hate crime.”

New York City Mayor Bill de Blasio issued a statement saying, “Whatever their source, those threats were an assault on our values and our people.”

“As the proud home of the world’s largest Jewish community, New York City will always stand ready to face down intolerance and stand up for our persecuted neighbors,” de Blasio added. “History teaches us that we can never be indifferent to the scourge of anti-Semitism, and we can never take lightly threats fueled by hate.”

“They found him. I think I stated a couple weeks ago that this would come to a successful conclusion, and it did,” NYPD Commissioner James O’Neill said. “People who engage in this type of behavior are going to suffer the consequences.”

O’Neill couldn’t confirm whether the suspect targeted specific locations in New York.

The threats led to criticism of the White House for not speaking out fast enough. Last month, the White House denounced the threats and rejected “anti-Semitic and hateful threats in the strongest terms.”

Last month, a Missouri man was charged in connection with at least eight threats against the ADL headquarters in New York City and JCCs nationwide. Prosecutors said the threats were made in an effort to harass and vilify his former girlfriend.

In New York City, anti-Semitic incidents – including bomb threats, swastikas on doors and subways, and threatening phone calls and emails — continue to skyrocket.

The latest NYPD statistics show a 177 percent increase in anti-Semitic hate crimes – 72 so far this year compared to 26 for the same period in 2016.

Even with the prime suspect arrested, security experts remain vigilant as we approach the Jewish holidays. The NYPD will increase the police presence at all Jewish institutions in the city for Passover.

“Now the Passover is coming, we may see copycats doing this, but will be investigated and dealt with accordingly as well,” Gomez said.

(© Copyright 2017 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)