A reward has been offered to help find the weapons used in an armed robbery and fatal shooting at a local grocery store early this week.

Spokeswoman Karleen Chalker said the Forsyth County Sheriff’s Office is putting up $2,000 “for information leading to the recovery of weapons used in the armed robbery and murder at the Ingles that occurred on Sept. 6 and any other evidence relating to that crime."

David Casto, 37, of Winder was shot to death Sunday night after three masked suspects entered the Ingles on Canton Road.

Casto was working as a security guard at the store, which was closed when the suspects entered through an unlocked rear door.

Chalker said the store has received an outpouring of support from members of the community who want to help Casto’s family.

As a result, a fund has been set up at United Community Bank. Donations can be made in the name of Shirley Burton at any of the bank's

locations.

Casto’s funeral is scheduled for 2 p.m. Saturday at Smith’s Funeral Home in Winder, with visitation set for 10 a.m.-2 p.m.

Within 24 hours of the shooting, the sheriff’s office had arrested four teenagers, two of whom are county residents, and charged each of them with armed robbery and murder in connection with the incident.

Sharod Johnson and Tyrice Kendall Adside, both 18 and of Forsyth County, have been denied bond as has the alleged gunman, Nakitta Holmes, 19, and a 16-year-old, both of Buford.

Johnson had worked at Ingles for six months as a cashier and told authorities he had been instructed by the other suspects to lure Casto and a female employee Sunday night to the back of the store.

Johnson’s and the female employee’s hands were bound with duct tape and they were taken by Adside and the youngest suspect to the store’s office while Casto and Holmes stayed in the cooler.

Sheriff Ted Paxton said authorities have identified Holmes as the gunman in a “cold-blooded, sadistic, execution killing.”

Paxton said Casto’s 9 mm pistol, which may have been the murder weapon, was taken from him during the robbery and authorities are also looking for at least two handguns and one shotgun.

In addition to the firearms, authorities want to find Casto’s bullet-proof vest, which he had worn to work the night he died.

Paxton said Casto was disarmed, his hands were bound and his eyes covered with duct tape before he was shot.

Another Forsyth County teenager, Darren Slayton, was arrested Tuesday.

The 18-year-old was charged in connection two counts of armed robbery in connection with the Aug. 26 holdup of the Chevron station at Hwy. 20 and James Burgess Road.

Authorities think one or more of the suspects arrested in Sunday night’s shooting also participated in that crime, as well as an Aug. 25 armed robbery at a local Waffle House and two armed robberies in neighboring Gwinnett County.

The sheriff has not ruled out additional arrests, but said authorities think they have all the robbery participants in custody.

Authorities have said that Adside, Johnson and Slaton likely became acquainted in high school -- all three graduated in 2010 -- though their connection to Holmes is not as clear.