The relatives of three men who died after catching Legionnaires' disease following an outbreak from a dirty hot tub on display in a DIY chain’s garden centre are suing the retailer.

Delivery driver Richard Griffin, 64, and customers William Hammersley, 79, and Harry Cadman, 71, died after contracting the disease in the summer of 2012.

A report by The Health Protection Agency (HPA) said the bug originated from a hot tub on display at the JTF Warehouse in Fenton, Stoke-on-Trent, which had not been filtered or cleaned for weeks. The Nordic Impulse Deep Hot Tub is believed to have exposed customers to the disease over a two-month period.

Bacteria formed in the stagnating water, causing the build up of Legionnaires' disease droplets. The particles became airborne and spread around the garden centre when the tub was turned on.

Father-of-two Mr Griffin, from Clayton, Staffordshire, was the first victim and died after spending a week in hospital. He had been delivering meat to the cafe, next to the display hot tub.

Mr Hammersley, from Chesterton, Staffordshire, and Mr Cadman, from Stoke-on-Trent, died from the disease a few days later. Both had been browsing the garden warehouse near the hot tub, which was displayed near the tills.

A further 18 people needed hospital treatment following the outbreak.

Thirteen claims for compensation have been settled out of court but the families of those who lost relatives and one of the survivors are pursuing their cases through the courts.

The Crown Prosecution Service is considering whether to pursue criminal charges.