Police are to discuss security with top officials of a supermarket chain following three robberies at a Bradford store.

Detectives are investigating after workers at the Netto store in Manningham Lane were tied up during a terrifying raid by two masked men last Friday night.

The robbery came just a month after a masked gunman forced his way into the same store and threatened staff.

And last May three staff were hurt when they were beaten and threatened with a handgun during another armed raid.

Another Netto store, in Greengates, Bradford, was also targeted last October when a machete-wielding robber stole cash.

Senior detectives are now planning to hold talks with head office staff from Netto to see if anything can be done to prevent any further raids.

The latest raid happened just after 8pm last Friday as staff locked up for the day.

Two masked men, who had hid inside the store, forced staff to open tills and hand over an undisclosed amount of cash.

They then tied up the employees and left them in an office before fleeing out of the back door. Police were alerted when one of the workers managed to free himself.

No weapons were used in the raid. Forensic experts are examining items removed from the store.

Detective Inspector Noel Devine, of Bradford North CID, said: "We need to sit down with Netto and see what security processes are in place and what can be done to prevent this type of offence happening again.

"We need to look at what systems are in place and what improvements have been or are being made.

"We have been speaking to their head office and liaising with other police divisions about the raid at Greengates.

"Luckily, no-one has been injured but any crime like this is of concern and is treated seriously.

"We have had three robberies at the same store, two in a month, and we have to look at what we can do to make things better, in partnership with Netto."

Det Insp Devine said the supermarket had to play its part in security.

"We can do so much but some responsibility has to lay with the company," he said. "We have to look at what can be done and some of it has got to be down to the store."

Det Insp Devine said robberies at business premises were rare in the Bradford North division but police responded to where crimes were occurring.

He said all lines of inquiry were being pursued into the robbery and appealed for any witnesses who might have seen the robbers fleeing the premises, by car or on foot, to contact them.

The raiders in the latest incident, both white, wore black balaclavas. One was between 5ft 9ins and 6ft tall and of medium build. He was wearing a dark green zip-up fleece and spoke with a local accent.

His accomplice was slightly shorter, slim, and was wearing a red and green hooped polo-neck jumper. He also spoke with a local accent and was carrying a holdall.

Anyone with information should contact Bradford North CID on (01274) 376259.

Kevin Mitchel, Netto regional manager, said: "Netto takes security very seriously and in particular the safety of our staff.

"We review and respond to all security related incidents and will do everything we can to support police in their investigation."