THE fire that destroyed several popular Glasgow businesses was ‘probably’ caused by an electrical fault, an investigation has concluded.

The blaze dubbed the ‘Victoria’s nightclub fire’ began in the ceiling void above Holland and Barrett at 94 Sauchiehall Street.

The report, obtained by ­Freedom of Information request by the Evening Times, details the events that led to the demolition of seven businesses, a hotel development and left a popular pub out of action for more than a year.

An assistant manager of Holland and Barrett was the first to call the fire service to report smoke coming from the roof of the ground floor shop around 8am.

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The staff member told fire investigations officers that she was in the office when she heard a loud “pop” in the ceiling void and could then smell smoke.

When first responders arrived on the scene they found “light smoke” at ceiling level throughout the ground floor of the shop and spoke to workmen involved in the construction of a hotel on the upper floors of 92 to 98 Sauchiehall Street.

Fire crews forced entry to Victoria’s nightclub on the first floor, where they identified large volumes of smoke coming from an area below the DJ booth.

After breaking into the floor, they saw fire within the floor void below.

When the area below the stage was exposed, the dynamics of the fire began to change with thick smoke escaping under pressure.

It was at this point that smoke started billowing from the building and became ­visible from the street.

Crews applied water to the fire that had then started to break through the ceiling of Holland and Barrett but, as conditions worsened, the station manager ordered a “tactical evacuation” at 9.25am.

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At its height, 120 firefighters were battling the fire that almost engulfed the historic neighbouring Pavillion theatre.

Efforts to bring it under control and dampen the building went on for five days – before a stop message was finally transmitted on April 27.

The building was then handed over to Police Scotland and later Glasgow City Council, but a significant part of Sauchiehall Street remained cordoned off until a complete demolition of the block from 92 to 106 eventually took place in June.

Due to the severe damage, it was deemed impossible to carry out a joint Fire Investigation or excavation of the site, but investigations officers attended the scene and carried out enquiries with firefighters and took statements from eye witnesses.

Among those interviewed were managers from the shops affected including Holland and Barrett, the tradesmen from the upper floors and the owners of the building.

Their findings revealed that an inspection of the fixed wire installation and an electrical test in Holland and Barrett in November 2014 found it be “unsatisfactory”.

A further test was carried out in March 2015, which was found to be satisfactory, but that remedial work was still required – deemed as “ongoing maintenance”.

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Part of the planned maintenance was to replace the main electrical board.

The installation certification was to last no longer than three years until the next test.

The report created by the Duty Fire Investigation Officer, states that construction work converting the upper floors of the building into hotel rooms was being carried out at the time but fire crews confirmed that the area was not involved in the fire during the early stages of the incident.

WM B. O’Neill concluded his report by stating the fire was likely to have been accidental in nature and caused by the failure of an electrical wiring or electrical equipment located in the ceiling void between the Holland and Barrett shop and Victoria’s nightclub.

As previously reported by the Evening Times, Scottish Fire and Rescue area commander James Hymas said that the blaze “probably” started on the upper floors.

A Holland & Barrett spokesman said: “We have not seen the report from the Scottish Fire and Rescue Service about this incident so unfortunately we cannot comment on its findings other than to thank them for their incredibly brave work in tackling this blaze.”