DAYTON, Ohio -- Police have captured a man who is accused of attempting to rob a Dayton Kroger store on Saturday. Now, investigators said the suspect may have been involved in other violent crimes.

Gregg Letner is being held in the Montgomery County Jail after police said he fired a shot at an off-duty Montgomery County sheriff's deputy outside the Kroger store and shattered a store window.

Investigators arrested 40-year-old Letner shortly after the shooting. They said during the alleged attempted robbery, Letner grabbed a clerk and used her as a shield.

Officers said they found the gun that Letner allegedly used in the shooting with the off-duty deputy who was working security inside the store.

Detectives said Letner may be involved in 10 other holdups, including an Aldi store robbery early on Saturday night on Linden Avenue. They also said Letner is being questioned in connection with four bank robberies in Dayton and Trotwood.

Investigators also believe Letner may be involved a robbery at an Aldi store in Englewood and a robbery that happened about two weeks ago at the same Kroger store.

At this time, investigators are considering what charges Letner may face.