Two security guards filling cash machines at Moor Allerton Sainsbury's last month were attacked by the three men wearing balaclavas

Both guards were hit over the head with an axe and one was stabbed in the chest.

The thieves made off with an empty cash box, which was later recovered.

Security firm Loomis has offered the cash to get people to come forward with information that can help snare the thieves.

Speaking at the Sainsbury's where the thieves struck on November 10 at 4.30am, Detective Chief Inspector Simon Bottomley told the YEP: "It is only by chance that no one died during this incident where the suspects showed a complete disregard for the lives of the two security guards they attacked with weapons.

"Fortunately the guard who was seriously injured is continuing to make good progress and I hope that today's announcement of a substantial reward will encourage someone to come forward and provide us with the piece of information which will help us to progress this investigation."

He added: "This was an extremely violent robbery in which a family man was almost killed and it's vital those responsible are taken off the streets and brought before the courts."

Police have released CCTV images of a silver, five-door Vauxhall Astra they believe may have been used by the robbers as a get-away vehicle.

Anyone with information about the robbery is asked to contact the HMET incident room at Belle Vue in Leeds via 0845 60 60 606 or call Crimestoppers on 0800 555 111