Feb. 12, 2010 -- Just over an hour's drive outside of Dallas, Tex., on 47 acres of fenced-in land on the banks of the Trinity River, America's longest-running law-enforcement standoff is taking place.

Members of a militant group barricaded themselves from the rest of the world in January 2000 and have remained there for 10 years.

John Joe Gray, a self-proclaimed "freedom fighter," is the man at the center of the standoff. The leader of the religious separatist group has warned that any government agents who attempt to remove them from the land should, "bring extra body bags."

Gray would fight to the death if authorities came for him, he said during a 2000 interview with ABC News' John Quinones

"I'm willing to die for it because how else could you live?" Gray said. "You know, what is freedom if -- they can take my land, you know. OK. They can take my life, but they can't take my freedom."

Watch the story on "Nightline" tonight at 11:35 p.m. ET

Ten years ago was also the last time Keith Tarkington saw his children.

"I haven't been with them all their life, but they still got me in them, you know?" Tarkington said. "I mean, ten years, that's ten Christmases, Easters, birthdays, all this I haven't been with my babies."

Tarkington's two sons, Samuel James and Joe Douglass, were taken by his ex-wife Lisa in April 1999 to the barricaded compound run by Gray -- who is Tarkington's former father-in-law.

Gray is wanted by Texas authorities for allegedly assaulting a police officer. During an altercation at a traffic stop, he allegedly tried to take a state trooper's pistol and bit him.

But Gray, a deeply devout Christian, was already well-known to law enforcement by then for his different -- even extreme -- views of government. He believes government has taken away too many of his God-given rights.

"I've put out literature about the new world order and what's going on," Gray said in an interview with ABC News in 2000. "And I've done that for years down there. And I think I upset a few people. They didn't like it."

Authorities believe Gray might be capable of acting on those views.

"There were things that he had on him that led me to believe that he posed a threat to the safety of people in another city," said Anderson County District Attorney Doug Lowe, who has been trying to bring Joe Gray to justice for 10 years. "That he was capable of building a bomb that he had plans to make a bomb to blow up a bridge in Dallas and that concerned me."

Waco Siege Haunts Law Enforcement

Though law enforcement wants to bring Gray to justice, a terrible specter lurks in the back of many of their minds: the Waco siege -- the stand-off at the Branch Davidian community in February 1993 that ended two months later in the fiery death of the sect's leader, David Koresh, and at least 76 of his followers, including about 20 children.

Waco is about 75 miles from the Gray compound in Trinidad.

Even though Tarkington has a court order granting him custody of his sons, the authorities have not moved on the compound. They've taken a cautious approach because of the passionate threats back then made by Gray and his militia to engage in an armed battle if there is an attempt to raid the compound.

"They say, 'We don't want another Waco.' David Koresh ... you know, he's just about like Joe Gray. We don't want another Waco epidemic on our hands,'" Tarkington said. "And I said, 'I don't either, but I want my kids back.'"

Law enforcement has been scarred by Waco, and by the 1992 incident at Ruby Ridge, Idaho, where Randy Weaver and his family confronted federal agents in a 16-month standoff that ended with the deaths of Weaver's wife and son and a U.S. Marshal.

"You look at things like Waco, you look at things like Ruby Ridge, and I'm not sure that it is worth going out there and taking that chance," said Henderson County Sherriff Ray Nutt, who's the fourth Henderson County sheriff since the standoff began.

"I'm not willing to risk my deputy's lives, and I really don't want to end up having to kill a bunch of them folks up there," he said.

'Nightline' Visits Gray's Compound

"Nightline" paid a visit to the Gray compound. Since we were told the group is deeply suspicious of outsiders, we carefully approached the gates hoping not to create alarm.

Sons Jonathan and Timothy Gray came out to see who was waiting at the locked fence. They talked with us for a while. We asked if Joe, their father, would also come out. He did, and told us his whole story for the next hour. They told us that they don't trust the government and don't believe that their story will be told fairly.

They also told "Nightline" they are free and live behind the fences according to God's law.

Gray said that on the compound, which has no electricity or running water, his family lives well, raises their own food and livestock, and prays. He and his sons told us they will defend this place with their lives, if it comes to that.

When we asked about Tarkington's children, Gray said they're no longer here. Most people in the area believe that the boys were taken by their mother to grow up among supporters of Gray.

"Ten years, my kids are getting older by the minute," Tarkington said. "We don't want to hurt nobody, I haven't seen my kids in 10 years, tell me something, who's getting hurt?"

Sheriff Nutt said he sympathizes with Tarkington, but assaulting the compound won't get his children back. He said that, in a sense, justice is being served.

"They're still out there. [Gray's] still in his own prison," Nutt said. "They've done no damage to anyone in the ten years they've been out there. They haven't won -- we just haven't been able to arrest them yet."

Even though it's been ten years, Lowe is convinced he'll eventually get his man.

"I don't think we're scared. I think that there's an obligation to be smart in this business and to use your bullets and fire when it makes a difference," Lowe said.

There's only one thing that would make a difference to Keith Tarkington.

"I ain't never going to give up looking for them and someday I'll find them," he said. "I just hope whoever has them takes good care of them and hope they know I love them. I'm not giving up."