Michael Ron David Kadar ... has been held in Israel since his March 23 arrest following an investigation by the FBI and Israeli police. His crimes were committed over the Internet from Israel, according to reports, at times using computers in other countries.

He's accused of using a powerful antenna to harness nearby Wi-Fi routers and employed voice-masking techniques to make the threats.

On April 21, Kadar was charged in US federal court in Florida with 28 counts of threatening calls and false information. He was also charged with three counts of cyberstalking in an indictment out of federal court in Georgia.

Kadar was not named in the Israeli indictment based on his age when the offenses occurred, but he was named in the US indictment.
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Kadar attempted to extort money from Delaware state Senator Ernesto Lopez and threatened to kidnap and kill the children of George Little, a former Pentagon and CIA spokesman, according to prosecutors.

Kadar also is accused of targeting several British Jewish schools from February 2016 to March 2017. The Jewish Museum in London was evacuated in February after a bomb threat that officials said was connected to Kadar.
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Kadar is accused of calling 48 police stations with fake emergencies, claiming people were being held hostage at certain addresses. He also threatened the Israel consulate in Miami, Florida, and a hospital in New Jersey.

Kadar's lawyer says he "suffers from a brain tumor that may have had an effect on his cognitive functions."

"This is a young person that because of his very, very serious medical condition didn't serve in the army, didn't go to high school, didn't go to elementary school," said Galit Bash, according to CBS News.

His lawyer has also said Kadar has a high IQ but very low emotional intelligence. His American-born mother told Israel's Channel 2 that Kadar has autism.

"He can't control it," she said, according to BBC News. "He can't think straight."