The lawyer for a man charged with fatally shooting an ice cream truck driver as children lined up outside says his client had been stalked for months by the man he's accused of killing.

Defense attorney Carl Somerlock said Tuesday that Brandon Brown had been trying to find and kill Larnell Lyles over a $20 debt. The lawyer's version of events was first reported by The Frederick News-Post.

Somerlock says Lyles was surprised Saturday when he went to buy ice cream for some children and saw Brown in the truck. The lawyer won't say whether Lyles shot Brown.

Police say they are investigating a motive. A man who was helping Brown sell ice cream has told police there was no argument before Lyles pointed a revolver and fired.