Primark says it is "deeply shocked and saddened" at a fire in its Belfast store.
A large fire broke out on the roof of the Bank Buildings at about 11.00am on Tuesday.
Some 14 appliances and 80 firefighters were at the scene in Castle Street.
Residents and businesses in the city centre were advised to keep their windows and doors closed.
The Northern Ireland Fire and Rescue Service say fire-fighting is ongoing and will continue "into the evening".
It also says the blaze has "extensively damaged" the building.
Fire has extensively damaged the Primark building in Belfast. Fire-fighting is ongoing & will continue into the evening. Whilst the incident is ongoing contingency measures are in place to ensure normal service delivery is maintained across Belfast. pic.twitter.com/2b1dLdOBfY
— NIFRS (@NIFRSOFFICIAL) August 28, 2018
Staff and shoppers were earlier evacuated from the scene.
Ambulance crews were also in attendance but there were no reports of any injuries.
In a statement, Primark CEO Paul Marchant says: "We are deeply shocked and saddened by the fire today at our Bank Buildings store in Belfast city centre.
"The safety and wellbeing of our customers, colleagues and construction team is of course the most important consideration and we are truly relieved that all were evacuated safely.
"We would like to thank the emergency services for their swift response and ongoing actions."
Image: Liam McBurney/PA Wire/PA Images
He adds: "Our store is housed in an iconic building and much loved by the people of Belfast.
"We would like to reassure our customers, colleagues and the wider community in Belfast that we are committed to working with the authorities and our building contractors to establish the cause of the fire."
Mr Marchant says the company is working closely with its team in Belfast to ensure they are "fully supported during this challenging period."
Just last week, Belfast Live reported that the store was seeking to hire 100 people to staff a major expansion, which was set to add 30,000 sq ft of retail space.
Smoke was seen billowing from the building from across the city.
Additional reporting: Jack Quann
