Primark is pursuing compensation in the region of £50 million three years after a mysterious fire razed its Leicestershire distribution centre to the ground, destroying half its stock in 15 minutes.

The value fashion retailer is suing the parties whose negligence it believes was responsible for the blaze at the warehouse in Magna Park in Lutterworth, Leicestershire, for unlimited damages. It is seeking damages from Magna Park Management (MPM), CPAM Commercial Property Asset Management, Atlas Fire Engineering and Young Contracting Company (Midlands).

Fire investigators were unable to determine what started the inferno, which was the biggest fire in Leicestershire’s history.

Shortly before 7pm on November 1, 2005, a fire swept through the single storey 440,000 sq ft warehouse, with witnesses describing explosions and fireballs as far afield as Northamptonshire and Warwickshire.

It took 15 fire engines and 80 fire fighters to control the fire after the sprinkler system failed to operate. No one was hurt and arson was not ruled out.

Primark – which started to operate from another warehouse on the site almost immediately after the incident – was praised for the swift implementation of its disaster management plan. The retailer chartered cargo ships and the world’s largest aircraft to replenish stock in time for Christmas.

It opened a larger, 650,000 sq ft warehouse on the site where the fire took place 10 months later.

This week, the retailer – which said it expected to report a like-for-like sales increase of 2 per cent in the second half of the year to September 13 – revealed it will be opening an additional 640,000 sq ft distribution centre at Thrapston in Northamptonshire by the end of the year, increasing its UK capacity by 50 per cent.