A fire chief has revealed that the Glasgow Union Street fire is believed to have spread "rapidly" through building voids before emergency services arrived, according to initial investigations.
Fire chiefs informed the Safe Glasgow partnership that the probe into the blaze, which devastated the iconic city centre building, remains ongoing, but officials have a "strong working hypothesis regarding the cause."
The massive inferno on March 8 appeared to originate in a vape shop at 105 Union Street and forced Glasgow Central Station to close for weeks.
Area commander Andy Kenna stated there is "no definitive timeline" for the completion of the final fire investigation report due to the "scale and complexity" of the incident.
However, he told the partnership that "initial investigation work indicates that the fire spread rapidly through concealed voids and cavities within the building."
"This has been exacerbated by the construction and historic alterations," he added, noting that evidence suggests the fire had "already developed within these voids before the arrival of emergency services, enabling vertical and horizontal fire spread across multiple floors prior to visible flame emergence."
The "working hypothesis" on the cause of the fire is being "refined in collaboration with investigative partners" and "remains confidential at this stage."
On-site investigation work has been completed, with the process now focused on "detailed evidence analysis including extensive data review and hypothesis testing to determine the fire's origin and cause."
The final report will be initially submitted to the Procurator Fiscal, with its public release "contingent upon the conclusion of any potential criminal proceedings."
Mr Kenna said: "Given the high profile nature of the incident, we are instructed to refer to the location strictly as 105 Union Street to avoid any misrepresentation or speculation regarding the premise or the fire's cause."
The Safe Glasgow partnership, which scrutinises police and fire activity, also heard that two internal debriefs on the response to the fire have been carried out to "capture the learning and support continuous improvement."
The fire caused part of the building to collapse and led to major disruption at Scotland's busiest railway station, with services affected for several weeks. Following a structural assessment, Glasgow City Council confirmed the remaining section of the building would be demolished on public safety grounds.
More than £10 million has been set aside by the Scottish Government to support recovery efforts following the devastating Union Street fire in Glasgow.
Earlier this month, councillors at a city administration committee meeting heard that £800,000 in grants awarded to businesses impacted by the fire had been funded through the council's capital programme.
A council officer told the committee that Scottish Government support would continue into the next financial year. They confirmed: "The Scottish Government has provided support in the form of £1 million of capital towards the clean-up operation and £10 million of revenue towards the economic recovery from the event."
