A Missouri man who avoided prison because of a clerical error and led a law-abiding life for 13 years said he is overwhelmed by the support he’s received since the story of his incarceration became public.

Meanwhile, the Missouri attorney general signaled that he would look for a way to take Cornealious “Mike” Anderson’s many years of clean living into account in attempting to resolve the “difficult situation.”

Anderson, who was convicted in 2000 of armed robbery for holding up a restaurant manager in suburban St. Louis, said he was cheered by inmates and guards at the Southeast Correctional Center in Charleston after his story appeared this week in news accounts.

An online petition urging his release has collected nearly 30,000 signatures, and one of Anderson’s attorneys said last week that his office has been flooded with calls from people who feel he has been wronged.

“It’s a little overwhelming and embarrassing to me, but I can’t thank people enough,” Anderson said. “Everybody here has been positive, the prisoners and the correctional officers. I’ve had other prisoners tell me it gives them hope.”

Anderson, who had never been convicted of a serious crime, was sentenced to 13 years. Authorities told him to wait for orders that would specify when and where he was to report to prison.

But the orders never came, so he didn’t go. Anderson suspected that his case had been overlooked and asked his former attorney what to do.

“He said it’s a mistake, and they’re going to figure it out — be prepared to be taken into custody,” Anderson recalled. “Day by day, month by month, year by year, time passed, and they never picked me up.”

So Anderson went about his life, never trying to conceal his whereabouts or identity. He married, divorced, married again. He raised three children of his own and a stepchild, owned and operated three construction businesses. He coached his son’s youth football team in Webster Groves, outside St. Louis, and ran the video operation at his church.

In July, Anderson’s sentence was supposed to end. When someone at the Missouri Department of Corrections tried to begin the process of releasing him from prison, the agency realized he had never been put behind bars.

Anderson said he was just getting up around 6:30 a.m. on a hot July day when he heard a bang on the front door.

“It was one of those, ‘Hey, open up the door!’ type knocks,” Anderson said. “I said, ‘Who is it?’ They said, ‘U.S. marshals. Open up, or we’ll knock the door down.’”

Anderson peered through the curtain and saw eight armed marshals.

“They had shields and helmets. They had the streets blocked off. I said, ‘You’ve got the wrong person.’ One of them said, ‘You remember 13 years ago when you were supposed to be incarcerated?’”

Anderson, 37, was alone at the time except for his 2-year-old daughter. The marshals immediately took custody of the girl. By noon that day, Anderson was at a state prison in Fulton. He stayed there until he was transferred to Charleston a day before Thanksgiving.

“It was a nightmare,” Anderson said. “The only thing I could think about was my wife and my kids.”

Attorney General Chris Koster said last week that his goal was to suggest a way for the court to balance the seriousness of Anderson’s crime with the clerical error made by the justice system and Anderson’s conduct since the robbery.

“All three factors deserve recognition in resolving this difficult situation,” Koster said.

Jaime Halscott, another of Anderson’s attorneys, said Gov. Jay Nixon’s office has also been asked to consider commuting the sentence or pardoning Anderson. Nixon’s spokesman did not immediately return a message seeking comment.

“He’s been rehabilitated,” Halscott said of Anderson. “There’s no need to protect the community, and even if you want your pound of flesh, he’s been in prison nine months. At the end of the day, there’s no good argument that this man should be in prison.”

Anderson’s attorneys filed an appeal in February calling his imprisonment unfair and unjust. Attorney Patrick Megaro said the last time something like this happened in Missouri was 1912, and that person was not forced to serve his sentence.