As a deputy director for the FBI's national security branch and an ex-CIA agent, Philip Mudd has interviewed terrorists and is considered a counterterrorism expert.

And still, Wednesday's school shooting in Florida left him in tears.

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Mudd, a CNN counterterrorism analyst, was speaking to Wolf Blitzer when he got emotional.

"I have 10 nieces and nephews who are talking about bump stocks," he said. "We're talking about legislation. A child of God is dead. Cannot we acknowledge in this country that we can't — we cannot accept this."

He continued before breaking down in tears: "I can't do it, Wolf, I'm sorr... — We can't do it."

Mudd's emotional response came after Wednesday's shooting at Marjory Stoneman Douglas High School in Parkland, Fla. At least 17 people were killed.