(CNN) -- Gov. John Hickenlooper, who this week signed some of the nation's tightest gun control measures into law, said Sunday he couldn't fathom why the son of one of his close friends would decide to shoot his state's prisons chief -- also a friend -- to death.
"I felt like I was caught in a nightmare I couldn't wake up from. All these things were happening to people that I loved. And they didn't seem to be connected in any way," Hickenlooper, a Democrat, said on CNN's "State of the Union." He added his own security was being bolstered in the aftermath of the crime.
"We know Evan was connected to the white supremacist group. We can't see clearly what a motive was," he continued, referring to Evan Spencer Ebel, whom authorities have linked with the slaying of Tom Clements, the director of Colorado's state corrections system.
Ebel himself died in a shootout with sheriff's deputies in Texas on Thursday. Investigators have told reporters that Ebel, a former member of a white supremacist prison gang, might have conspired with other inmates to kill Clements.
Clements earned widespread recognition not only for prison reforms but also for a crackdown on prison gangs, including the one Ebel is said to have belonged to.
By all accounts, Ebel came from a privileged upbringing. His father, Jack Ebel, an attorney and former oil executive, counts Hickenlooper among his friends. The two met in the 1980s while working for the same firm.
"From the beginning his son just seemed to have this bad streak -- this streak of cruelty and anger," Hickenlooper recalled to CNN chief political correspondent Candy Crowley. "And yet, they did everything they could. They worked with Evan again and again, but to no avail. He had a bad, bad streak."
Clements was also a friend, Hickenlooper said, and one of the "elder statesmen" in Colorado's government.
"To have two people connected, two people I know so well and love so deeply to be connected by this, it's inexplicable," he said.
This week, Hickenlooper signed into law new gun control measures requiring universal background checks for gun sales, restricting the size of ammunition magazines and making buyers pay for their own background checks.
The laws, which at one time would have seemed impossible in Colorado, came after a spate of deadly shootings in the United States, including the movie theater massacre in Aurora, Colorado, last summer.
Lawmakers in Washington are also debating new gun control laws, though a ban on assault weapons pushed by some Democrats was scuttled this week when it wasn't included in legislation headed to the Senate.
A ban on assault weapons, along with other measures like improving background checks, make for "tough sells" in states like Colorado, where gun ownership is a way of life, Hickenlooper said.
"They deeply believe that their guns and the Second Amendment are critical parts of American life," he said Sunday. "And their integrity and honesty and conviction, you can't challenge that."AlertMe