Good Samaritan Who Saved Trooper from Attacker Speaks Out: 'I Can't Stand By and Watch'

Thomas Yoxall was driving on a remote highway January 12 when he saw Trooper Edward Andersson being assaulted.

A passing motorist who stopped an assault on a cop by pulling a gun on an assailant after the officer was ambushed has spoken out.

Thomas Yoxall was driving on a remote Arizona highway January 12 when he saw Trooper Edward Andersson being assaulted. The quick-thinking gun owner retrieved his weapon and opened fire on the assailant, likely saving Andersson.

Watch: 2 Police Officers Killed in Patrol Cars While On Duty in Ambush-Style Attacks

While speaking for the first time publicly on Tuesday, Yoxall told reporters he was just doing God's work when he fatally shot the man, identified as Leonard Pennelas-Escobar.

"I firmly believe I was put there by God," Yoxall told reporters. "It’s who I am — I can’t arbitrarily stand by and watch a tragedy like that unfold without doing what I can to intervene and stop it... I responded the only way I know how to respond, and that’s to act.

Arizona's "defense of third person" law allows someone to use deadly force against another who is threatening or injuring a third person. It was not unusual that the 43-year-old was armed in the gun-friendly state with loose regulations on firearms.

The bizarre story unfolded after Trooper Andersson was dispatched to the scene of a 911 call outside Phoenix, where a driver said he'd been shot at from the median of Interstate 10.

While en route to the area where the call was placed near Tonopah, the 27-year veteran of the Department of Public Safety came upon a car that had overturned, causing a woman to be ejected from the vehicle and killed.

While he placed road flares around the scene, Andersson was shot by a suspect who then physically assaulted him.

"A physical fight between our trooper and that suspect then ensued," DPS Capt. Damon Cecil said at the time.

Meanwhile, Yoxall happened by and saw Pennelas-Escobar "getting the better of" the trooper. Yoxall stopped and asked the trooper if he needed help.

The trooper said yes, prompting Yoxall to retrieve his gun.

Read: Man Wears Sign Supporting Suspected Cop Killer Outside Florida Sheriff's Office: 'God Bless the Shooter'

“It was very visceral and instinctive — I had to help,” said Yoxall.

Despite his heroism, Yoxall said it's not always easy knowing he took one life to save another.

"Doing the right thing sometimes has a price, and that price is severe," he said. "This is something I will live with, but I wouldn’t change it because another man gets to go home to his family."

Yoxall was previously charged with felony theft in connection to a 2000 incident in which he admitted to stealing electronics from a group home where he worked, The Arizona Republic reported.

He petitioned the judge to reduce his felony conviction, stressing that he was eager to restore his right to bear arms. 

"Before this incident, I was an avid shooter," Yoxall wrote in 2003. "… I miss owning a gun. I miss shooting with my friends as well as my son. I hope, if nothing else, you will reinstate my civil rights to include the right to bear arms once again."

A Superior Court Judge in 2003 vacated Yoxall's guilty judgement and resorted his right to possess a firearm, according to the Republic.

Yoxall, who acknowledged at a media event that he has a "past," said without elaborating that "those moments of poor judgement have not dictated my future."

"I feel that it’s a right and a privilege to be a private gun owner, and with that right and privilege comes a great responsibility," he said, the Republic wrote. 

The trooper suffered gunshot wounds to the right shoulder. He underwent surgery and has since been sent home, where DPS director Frank Milstead told reporters Andersson is recovering and in good spirits.

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