At least six workmen were injured today when a building under construction collapsed in Belfast.
Concrete was being poured into an area of the second floor that which apparently gave way. A number of workers had to be pulled free from falling steel girders, scaffolding and rubble.
All six workers were detained in the Royal Victoria Hospital in Belfast with broken limbs and other injuries.
It is understood the two most seriously injured workers are Polish and employed by a company from Omagh, Co Tyrone.
The collapse happened on Victoria Street, near the centre of Belfast, where a new office block for the Northern Ireland Law Society was being built. It is due to open in 2009.
Sniffer dogs were used to ensure no one else was trapped within the site where up to 60 workmen are employed in the construction of the building which will eventually have seven floors, ground floor shops and underground parking.
The Health and Safety Executive closed down the site, ordered all workers off and said no resumption of work would be allowed until they had carried out a full investigation, something which a spokeswoman said could take several days.
Four people have died on construction sites in Northern Ireland so far this year and the construction union UCATT warned the growing use of casual workers on sites was increasing safety problems.