Washington (CNN) Fred Guttenberg, the father of a slain Parkland student, said he had approached Supreme Court nominee Brett Kavanaugh at his confirmation hearing Tuesday in an attempt to appeal to him "as a dad," but when he extended his hand he was ignored by the judge.

"I simply said, 'Hi, my name is Fred Guttenberg, I'm the father of Jaime Guttenberg, who was murdered in Parkland,' " Guttenberg told Kate Bolduan on CNN's "Erin Burnett OutFront." "As soon as I got to the 'murdered in Parkland,' that's when you saw him turn and move and walk the other way."

White House deputy press secretary Raj Shah addressed the moment on Twitter earlier Tuesday, saying, "As Judge Kavanaugh left for his lunch break, an unidentified individual approached him. Before the Judge was able to shake his hand, security had intervened." He added that video "clearly shows security intervened" when Kavanaugh was approached.

A source familiar with the encounter said Kavanaugh did not know who Guttenberg was and that security intervened to end the exchange before there could even be a handshake. The source said Kavanaugh's security detail quickly stepped in because they did not know who the person was.

Guttenberg attended the confirmation hearing as a guest of Sen. Dianne Feinstein, a California Democrat, who introduced him at the hearing.

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