Concord PD Cracks Round 1 Robbery Case – Robbers Had Inside Help

One of our most widely read stories in recent weeks concerned the robbery of the Round 1 Amusement Center at the Sun Valley Mall in Concord, an aggressive takeover-style robbery that ended with employees zip-tied with their hands behind their back and an $11,000 take for the thieves.

During the May 12 robbery, masked gunmen entered the arcade through an unsecured back door, occupied a safe room and forced an employee to open it before looting the contents and escaping into the night.

After a three-month-long investigation, authorities Wednesday announced the arrests of two alleged participants: Vincent Timmons, 37, who investigators said was one of the masked gunmen, and Vallejo resident Gary Dillahunty, 45, a security guard who worked at the arcade and allegedly helped plan the heist. Both men have criminal records and alleged ties to a California prison gang, investigators said.

Investigators determined that the thieves accessed the business through a normally secured employee entrance, eventually uncovering a conspiracy between Round 1 security guard Dillahunty, who was working that night, and the crew of thieves.

A search warrant was executed at Timmons’ home in San Francisco last week, according to police. Evidence linking Timmons to the Round 1 robbery as well as an illegal assault weapon, a hand gun, and a large quantity of cocaine was found. Timmons, who is on parole for kidnapping, was located at the home and arrested for robbery.

On Tuesday, with the assistance of the United States Marshals, 43-year-old Gary Dillahunty, who is on parole for assault with a deadly weapon, was located at a home in Vacaville. He was arrested on an outstanding arrest warrant for the Round 1 robbery as well as a warrant for violating his parole.

The Contra Costa District Attorney’s Office has charged both men with multiple felonies including robbery, conspiracy, and kidnapping. They both remain in custody at the Contra Costa County Jail.

The investigation into others involved with this robbery, including the second masked suspect continues, police said.

The security guards working at Round 1 at the time of this robbery were employed by an outside security contractor. This information is being shared with the California Bureau of Security and Investigative Services, a regulator of the private security industry.

Anyone with information about this case may call the Concord Police Department Tip-line at ‪(925) 603-5836‬.