By Letitia Stein and Colleen Jenkins

(Reuters) - For the cartoonist whose portrait of Muhammad won a Texas contest, the police killing of two gunmen outside the meeting place was justice.
             
"They came to kill us and died for it. Justice," artist Bosch Fawstin tweeted on Monday.
             
Fawstin's winning entry depicts a sword-wielding Prophet in a turban shouting, "You can't draw me." In reply, a cartoon bubble portrays the artist, his hand grasping a pencil, as saying, "That's why I draw you."
             
The American Freedom Defense Initiative (AFDI), sponsor of the Sunday night event, gave Fawstin, a Bronx, New York-born, former Muslim, $12,500 in prize money and introduced him to the crowd as a courageous and righteous man. 
             
The Southern Poverty Law Center, which includes AFDI on its annual list of U.S. hate groups, plans to add Fawstin to its 2016 report, Heidi Beirich, director of the tracking effort, told Reuters on Monday.
             
She said he would have been listed previously, but the center did not know Fawstin's location. The organization has since learned that his website is registered in New York City.
             
“He’s like the artist of the movement,” Beirich said. “His views, they are hate views.” She said his website is "virulently ugly" in its anti-Muslim views.
             
When reached by phone on Monday night, Fawstin said Sunday's incident made him fear for his safety, but he would continue his work.
             
"It definitely is concerning. You do your work and people out there want to kill you for it," he said. "I understand the threat, but I'm not going to be cowed by it. I still intend to go up there and I still intend to speak out."
             
Fawstin, who said he is atheist, laughed when asked about the law center's report: "So they want to put a cartoonist on there who doesn't act out violently? Go for it."
             
For many Muslims, drawings of Muhammad are offensive.  At the Texas event, Fawstin voiced another view. He said the issue was free speech.
             
“It’s about us not being told what we can or can’t do as Americans, as free people, as Westerners,” he said in a website video from the event.
             
Fawstin invented the character “Pigman,” the alter-ego of an ex-Muslim named Frank Warner, who ruthlessly puts down jihadists wherever he finds them, he told the conservative FrontPage Magazine website in 2011.
             
The son of Albanian Muslim immigrants, Fawstin has in interviews recalled drifting from the religion and developing an interest in drawing and comic books as a child. 
             
He said he began drawing comics seriously in his late 20s after taking night art classes. The Sept. 11, 2001, attacks were for him a turning point, he said. 
             
But much about him remains a mystery, including whether Fawstin is his real name, Beirich said. In Sunday's webcast, his interviewer says Fawstin traveled from overseas. “From somewhere, and I’m here,” he responds.
              
(Additional reporting by Curtis Skinner; Writing by Howard Goller; Editing by Toni Reinhold)