Investigators say a tipster pointed them to the man charged this week in a 13-year-old fatal bank robbery, but the suspect coincidentally came to them on his own on an unrelated matter. And authorities say they used that complaint as a way of surreptitiously collecting his DNA.

Richard Leon Wilbern was arrested Tuesday when he went to meet with FBI agents in Rochester to discuss his fraud complaint.

Wilbern had been on the FBI's radar since March, when a caller reported that he'd robbed a bank on the Xerox Corp. campus in 2003, fatally shooting one customer and wounding another.

Federal authorities said Wednesday they matched DNA from an umbrella left at the bank to a sample they got from Wilbern when he met with them about his complaint.

Wilbern appeared in federal court Tuesday and requested a public defender.