Laurence Key of Stuart, Florida was arrested Tuesday after allegedly threatening to kill Rep. Brian Mast (R-FL) and his three young children over the Trump administration’s immigration policy.

Key reportedly phoned Rep. Mast’s D.C. office on Monday, warning the intern who received the call that he was going to “find the congressman’s kids and kill them,” say court documents filed in U.S. District Court.

“If you are going to separate kids at the border, I’m going to kill his kids,” Key said in one of 478 calls to Mast’s office, according to the filings. Key also allegedly contacted Senators Bill Nelson and Marco Rubio.

“Key told an FBI investigator and Martin County sheriff’s deputy he never threatened to kill Mast’s children, but admitted he said ‘Mast should be separated from his kids’ if he supported the Trump administration policy,” reports Treasure Coast Palm.

The Stuart man was charged with threatening to kidnap or injure a person and is scheduled for arraignment on July 2 in St. Lucie County, Florida.

Rep. Mast, an Army veteran who lost both his legs while serving in Afghanistan, has not issued a statement on the incident.