A £25,000 reward is being offered for information that leads to the arrest and conviction of those involved in a robbery at a bank in Quedgeley last week.
The reward has been donated by HSBC, whose branch at Olympus Park was ram raided last Friday (October 5) morning.
A Nissan Navara was driven into a glass door and two men wearing balaclavas entered the building and snatched money being loaded into a cash machine, though to be in the region of £100,000.
The Navara that detectives believe was used in the robbery was found abandoned in Carters Orchard in Quedgeley on Sunday (October 7).
Detective Chief Inspector Marc Flannery said: "We're hoping that this money may convince someone to come forward who was reluctant before.
"These offenders need to be stopped before they strike again and possibly hurt someone."We're continuing with a number of forensic and other inquiries but still need information from the public.
"Please think back to that morning and call us if you can help.
"No matter how small a detail you think it is we want to hear it."
Officers are keen to speak to customers who tried to use the ATM, which was out of service, between 9am and 9.25am.
Police would also like to hear from anyone who saw the green, double cab Nissan Navara (registration number SV03 GVL) in the Carters Orchard area or nearby between 9.20am and 9.30am on the day of the ram raid.
Anyone with information should ring 101, quoting incident 120 of October 5.
Or contact Crimestoppers, anonymously, on 0800 555111, or via www.crimestoppers-uk.org