Fire investigators have been given access to the Mackintosh Building at Glasgow School of Art four months after a blaze tore through it.

Demolition contractors have been taking down sections of the Mackintosh to be preserved for a future rebuild, after a devastating fire in June.

But concerns have been raised by residents neighbouring the iconic building who are angry it has taken to long and fear the cause of the blaze may never be identified.

Dr Iain Sanderson, programme leader of Fire Risk Engineering at Glasgow Caledonian University, said the desire to preserve the building had led to delays.

He said: "With everything that is exposed to the elements there is some degree of deterioration.

"As time progresses things will deteriorate, but there are ways of investigating.

"Normally you would get access quicker than they have but people wanted to preserve the building.

"Because of the wish and desire to preserve the building it will have caused substantial delay."

Questions posed to the chief fire officer Alistair Hay by residents and the community council addressed fears the delay would "impact and likely cripple" the investigation.

They asked: "What is the opinion of the SFRS regarding the apparent conflict of interest between the Art School having control of the building, whilst altering the structure itself through their contractors, potentially destroying valuable technical evidence pertaining to the origin and spread of the fire?"

Assistant chief officer of the Scottish Fire and Rescue Service, David McGown, said: "The investigation into the fire that took hold of the Glasgow School of Art, O2 ABC and surrounding buildings remains ongoing.

"Following work to ensure the safety of those working within the structure, our fire investigation experts have now been able to gain access to the inside of the Mackintosh building."

"Our specialist team continues to work alongside our police partners, and through a high volume of information from various sources.

"I would like to stress once again that this is a very complex process and will therefore take time."

A spokesman for the Art School said: "We have been working to get to the stage where the building is safe to be accessed.

"We have been working from day one with the Scottish Fire and Rescue service on the investigation."

Pauline McNeill, Glasgow Labour MSP, said: "Residents are already anxious and they feel the lateness might compromise the investigation."

On November 2, it was announced that director of the GSA, Professor Tom Inns, would step down from the role he held for five years.

Prof Inns said: "The Glasgow School of Art is an exceptional place, in stepping down I will miss the creative energy of staff and students enormously, and I wish them all well as the Institution approaches its 175th Birthday in 2020.

"Since the fire in June 2018, just months before the building was to be handed back to GSA, we've worked tirelessly to stabilise the building as quickly as possible to minimise disruption to our local community, and to reopen our own campus for the new academic year.

"The Board of Governors is now developing plans to rebuild the Mackintosh Building.

"I have led GSA through the challenges of fire recovery twice and a restoration of the Mackintosh Building, whilst simultaneously extending GSA's global reputation, delivering growth, opening up opportunities for disadvantaged students and transforming other parts of GSA's estate.

"It is now time for a new Director to work with the Board to deliver the future vision for GSA."