An interview with Sen. Ted Cruz (R-TX) on Tuesday night went off the rails after a CNN anchor claimed that authorities still don't know the motive of Charlie Kirk's killer.

Cruz joined CNN's Kaitlan Collins on "The Source" to discuss the latest developments in the investigation into Kirk's assassination. Kirk, the co-founder of conservative student group Turning Point USA, was killed on a Utah university campus last Wednesday during a talk.

Cruz claimed the alleged shooter was motivated by far-left ideologies and "transgenderism." Collins rebutted that authorities are still working to determine the motive.

"We don't have a motive yet," Collins said. "We don't know yet. We've heard what the Governor had to say today, and what the FBI Director had to say."

"Of course, we know the motive!" Cruz shot back. "Really? That's CNN's position? He just happened to fire the gun in celebration."

"Senator, that's not what I said," Collins replied. "I said law enforcement hasn't laid out a direct motive. They've laid out a lot of evidence of the messages and what has been said."

"He was a left-wing activist who hated Charlie Kirk!" Cruz said.