(CNN) - Former Rep. Ron Paul, normally known for his online popularity, drew criticism Monday for asserting a political opinion in a tweet about the Navy SEAL who was killed at a gun range this weekend.

The three-time presidential candidate and longtime congressman from Texas is known for his staunch opposition to U.S. military involvement. While he doesn’t describe himself as an “isolationist,” he has won favor among libertarians for opposing military intervention in other countries.

Kyle, 38, had claimed a record number of sniper killings in Iraq and said in an interview that he had no regrets about the 160 people he shot during his five combat tours in Iraq.

The former SEAL with two silver stars was an outspoken defender of Second Amendment rights and also helped form a foundation that assisted military veterans struggling with post-traumatic stress disorder. Kyle was killed along with another veteran, Chad Littlefield. The two had arrived at the shooting range together Saturday with the suspect, Eddie Ray Routh.

In a post to Facebook Monday night, Paul elaborated more on his comment.

“As a veteran, I certainly recognize that this weekend’s violence and killing of Chris Kyle were a tragic and sad event. My condolences and prayers go out to Mr. Kyle’s family,” the post stated. “Unconstitutional and unnecessary wars have endless unintended consequences. A policy of non-violence, as Christ preached, would have prevented this and similar tragedies. -

While Paul has also been known as an advocate for gun rights, his comment earlier on Twitter quickly drew fire for going over the line.

More: Ron Paul’s Controversial Tweet About Slain Navy SEAL Political Ticker Blogs

Paul supporter “Bill Hicks” put it more succinctly in the comments:

Ron Paul is on the money, and has the guts to say the truth.

War hero? No. A war thug, nothing more. Just like that vet who’s on trial for murdering civilians, Chris Kyle was nothing more than a murdering thug. He was part of an illegal invasion of a sovereign country based upon lies (where are those WMDs Dubya)? He was assassinating citizens trying to protect their country, nothing more. In short, a murderer.

I am glad this filth met the fate he deserved, a fate ordained by the Christian God these types pray to. Live by the gun, die by the gun.

This man did NOT protect my freedoms. In fact, he made me LESS safe in the world today. I have no sympathy for him, for his family, or his degenerate conservative minions. Rot in Hades pal - you’ve earned it.