Story highlights Deryl Dedmon says he was "ignorant and full of hatred" when he killed Anderson

The victim's sister says her family is praying for "racial conciliation"

The prosecutor says more charges and arrests are coming

Dedmon has been sentenced to two concurrent life terms

A white Mississippi man has been sentenced to life in prison for the 2011 murder of an African-American man, with the judge calling it an inexcusable, "despicable" crime.

Deryl Dedmon pleaded guilty to murder and a hate-crime charge before a judge in Jackson on Wednesday afternoon, admitting to the June killing of James Craig Anderson. Hinds County Circuit Judge Jeff Weill sentenced him to two concurrent life terms, saying, "This craven act isn't who we are."

"Whatever excuse you offer, forget that. There is no excuse," Weill said. He added, "The state of Mississippi condemns this despicable crime."

Dedmon, 19, told the judge that he was a "changed man" who had found religion since his arrest.

"I wish I could take it all back," he said, adding, "I was young and dumb, ignorant and full of hatred. I chose to go down the wrong path."

Dedmon is also expected to plead guilty to still-undisclosed federal charges Thursday, three sources with knowledge of the case told CNN -- the first indication that a federal case was pending in Anderson's death. Officials would disclose no details, but Hinds County District Attorney Robert Shuler Smith said he expected other charges -- and other arrests.

"This is just the beginning," Smith said.

Anderson's killing prompted several large marches and prayer vigils in Jackson, a city of about 537,000 people. His sister, Barbara Anderson Young, said during Wednesday's hearing that her family was praying for "racial conciliation."

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"These last months have been very difficult," Young said. "We cried. We wept. We reminisced about our beloved brother, Craig, a loss I cannot even explain. Craig was a big-hearted person who loved his fellow man."

Anderson died after he was beaten and run over by a truck driven by Dedmon, according to police. Dedmon was part of a group of seven white youths from largely white Rankin County who decided to "go f**k with some niggers," after a night of partying and drinking, law enforcement officials have said, quoting some of the suspects in the case.

Smith has said the evidence indicated the suspects, who ranged in age from 17 to 19, "went out with the intention to harm and, in this case, kill a black man." According to investigators, they drove 16 miles in two vehicles from Rankin County to Jackson, where after exiting the highway, they found Anderson alone in a parking lot about 4 a.m. on June 26.

The white men allegedly beat Anderson repeatedly, yelling racial epithets. After the beating, Dedmon drove his Ford F-250 truck over him, leaving him to die, according to what some of the teens cooperating with police have told authorities.

Anderson's death drew national attention after CNN first reported it and aired exclusive surveillance video of the killing, captured by a parking lot security camera in a Jackson suburb.

A second man, John Aaron Rice, was initially charged with murder, but a judge reduced the charges to simple assault because Rice was not believed to be driving the vehicle used to kill Anderson.

For months, lawyers had been working behind the scenes in Jackson, where Dedmon is being held, fighting over a change of venue in a possible trial. Smith had hoped to have a trial in Jackson, where the crime occurred and which is largely black. But defense attorneys wanted to move the trial to an area with a larger white population, the law enforcement officials said.

Authorities believe Dedmon led and instigated the attack. On a sweltering Mississippi night in June, a gang of youths climbed into Dedmon's green truck and a white SUV and drove to the western edge of Jackson. They would have seen Anderson immediately as they exited the highway, officials said. He was standing in a hotel parking lot just beyond the exit ramp.

On the videotape obtained exclusively by CNN, the group pulls into the parking lot and stops where Anderson is standing, although he is just off camera and not visible.

The young men can then be seen going back and forth between their cars and Anderson. Witnesses told authorities this is when Anderson's beating took place, as the white youths yelled racial epithets, including "white power."

Authorities allege Dedmon and many of the other teens pummeled Anderson repeatedly as he crumpled to the ground, although this is not visible on the tape. After the beating, some of the white youths left, and others got into the green Ford truck.

At this moment, Anderson becomes visible on the tape as he staggers into view and walked toward the truck.

"Defendant Dedmon drove the F-250 out of the parking lot and turned right onto Ellis Avenue," the lawsuit says. "Just as Dedmon turned right, his headlights shone directly on Anderson, who, having been severely beaten, was stumbling in a grassy area near the motel's entrance. Dedmon accelerated, drove onto and over the street curb, and struck Anderson with the front of the F-250."

Shortly afterward, Dedmon allegedly boasted and laughed about the killing, according to statements some of the teens made to detectives. "I ran that nigger over," he allegedly said in a phone conversation to the youths in the other car.

"He was not remorseful," Smith said. "He was laughing, laughing about the killing."

But during a bail hearing last year, Dedmon's attorney told the court he saw nothing to back up the "racial allegations."

The U.S. Justice Department had been looking into the death as a possible federal hate crime and assisting local prosecutors. Federal investigators also have been digging for months into other possible crimes in the area committed by Dedmon and others that might show a pattern of racial violence.

Anderson's family had asked state and federal officials not to seek the death penalty against Dedmon or any other youths who might be charged in the case, saying they oppose capital punishment in part because of their religious faith. The family also filed a wrongful death suit against all seven of the white youths who were present at the beating of Anderson. The Southern Poverty Law Center, a nationally recognized organization in Montgomery, Alabama, that opposes racism and intolerance, joined in the lawsuit to help the case, joining forces with the family's attorney, Winston J. Thompson III.

"James Anderson lost his life for no other reason than the color of his skin," said Morris Dees, chief trial counsel for the law center . "Those responsible must be held accountable for their callous and deadly actions. We are filing this lawsuit today to ensure his family gets a measure of justice."

Anderson, a line worker at a Nissan plant, sang in his church choir, Thompson said. He is survived by his partner of 17 years.

"He was just a pillar of the community," Thompson said. "He paid his taxes on time; he went to work, came home -- he was just an average, ordinary citizen, good guy, wonderful gardener."