A man from Stuart, Florida, has been arrested after threatening to kill Republican Rep. Brian Mast’s children over President Donald Trump’s family separation policy.

Lawrence Key was arrested after allegedly making a threatening call to Mast’s Washington office on Monday, WPTV reported.

Key is accused of telling an intern who answered the phone “I’m going to find the congressman’s kids and kill them. 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.

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

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

In addition to the call on Monday, Key has contacted Mast’s office a total of 478 times, authorities said. He also contacted the offices of Florida Sens. Marco Rubio and Bill Nelson on Monday, they said.

Key is being held in the St. Lucie County jail as he awaits a bond hearing.

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