KANSAS CITY, Mo. -- The family of a killed man was upset Tuesday after a man accused of killing him made a surprise move in court.

Charged with first-degree murder, Fabian Brown was led into a courtroom where jury selection was supposed to start in his trial Tuesday. Instead, Brown agreed to plead guilty to a lesser charge.

The prosecutor accepted the deal, even though the victim's family was against it.

Robert Osborn was shot and killed on Nov. 20, 2005.

Osborn was riding his bike home from work when -- in court Tuesday -- Brown said he fired two shots at Osborn and missed, then another man, Rapheal L. Willis, now 22, shot Osborn with a shotgun, killing him.

The pair had set out to rob someone, Brown said in court Tuesday.

Brown and Willis have both accused each other of killing Osborn.

Osborn's two brothers were saddened by the plea deal, they said.

"There was no reason for this crime. As we understand it, they were out just to kill someone for the fun of it," said Rick Osborn, one of the victim's brothers.

The victim's brothers also were disappointed prosecutors decided to make an agreement, they said.

"Families do want the maximum, and as a prosecutor, we have to make sure we can obtain a conviction," said Prosecutor Kevin Harrell.

Instead of life in prison, the maximum sentence brown could get is 20 years in prison.

"If these two were so bored that they would hunt my brother down and kill him simply out of boredom, they need to set in a jail cell by themselves for the rest of their lives," said Ron Osborn, Robert Osborn's other brother,

Brown's sentencing is scheduled for Nov. 17.

Willis pleaded guilty in August to second-degree murder and armed criminal action. He is scheduled to be sentenced in October.