Maryland's top federal prosecutor declined to comment yesterday on an FBI investigation of missing money that had been introduced as evidence at a bank robbery trial in U.S. District Court in Baltimore.

U.S. Attorney Thomas M. DiBiagio's office is under scrutiny because federal prosecutors and the FBI agents assigned to the bank robbery case would have been directly responsible for securing the cash evidence.

As much as $38,000, most of it in $20 bills, was discovered missing after the two-week robbery trial ended late last week, law enforcement sources said. FBI officials confirmed this week that they are investigating.

DiBiagio, who has made polishing the reputation of the U.S. attorney's office a priority, would not comment on the investigation yesterday or say why he would not address it.