A mistrial was declared Thursday in the case of a man from Stuart, Florida, who was charged last year for threatening to kill Rep. Brian Mast’s children over the Trump administration’s family separation immigration policy.

Laurence Key, 68, is charged with one count of communicating a threat to kidnap or injure a person. But the trial that began Monday in Miami was declared a mistrial after the jury was hung, TCPalm reported, citing court documents and a spokeswoman for the U.S. Attorney’s Office in the Southern District of Florida.

Key was arrested in June 2018 after allegedly making a threatening call to Mast’s Washington office. He had been calling Florida congressional and Senate offices all day, he told authorities, comparing the Trump administration to the Nazi regime in Germany in the 1930s.

“I’m going to find the congressman’s kids and kill them,” Key is accused of telling an intern for the Florida Republican at the time who answered the phone. “If you’re going to separate kids at the border, I’m going to kill his kids. Don’t try to find me because you won’t.”

After the intern reported the call to a supervisor, the FBI began an investigation and Key was arrested shortly thereafter, documents show.

Key denied making the threat to FBI agents and a Martin County deputy, but said if Mast supported Trump’s family separation policy, the congressman should be separated from his children.

In addition to the call to Mast’s office for which he was charged, Key had contacted Mast’s office a total of 478 times previously, authorities said.

Key had been active with the Martin County Democratic Party and volunteered with the local Planned Parenthood, a friend told WPTV last year. Other friends described him as a “gentle soul” and didn’t believe he would hurt anyone, the station reported.

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