Three men accused of a string of bank robberies were indicted Friday, but authorities said they will not face federal charges in the death of an FBI agent who was shot, apparently by a colleague, while some of the suspects were arrested.

But if the men are convicted, the death of Special Agent Barry Lee Bush could be considered at sentencing, potentially adding decades to prison terms.

Bush was part of a stakeout attempting to catch men believed responsible for four armed bank robberies in central New Jersey that netted nearly $90,000.

The FBI has said it appears Bush was shot April 5 when another agent's weapon discharged accidentally outside a bank authorities say the armed suspects intended to rob.

There is no federal law that would allow the men to face indictment in connection to the agent's death, in part because the death did not take place on federal property, said Michael Drewniak, a spokesman for the U.S. attorney's office, which presented the case to a grand jury in Newark.

Each of the three men indicted — Wilfredo Berrios, 28, Francisco Herrera-Genao, 22, and Efrain Lynn, 21 — faces a single conspiracy count, four bank robbery charges and four weapons charges.

Berrios and Herrera-Genao also face a charge of attempted bank robbery and a weapons charge stemming from what authorities said was a bid to rob the PNC Bank in Readington the day Bush was shot.

A fourth suspect, Michael Cruz, was not indicted, but appears to be named as a coconspirator.

Messages seeking comment from lawyers for the four men were not immediately returned.

Berrios and Cruz were arrested outside the bank where Bush was shot. Herrera-Genao fled on foot and was captured nearly a day later a few miles away. Lynn was arrested elsewhere.

All four, who lived in New Brunswick, have been held in federal custody without bail.