Seven people remain in hospital following this morning's explosion at a tyre recycling plant in Co Louth.
The blast followed a fire which broke out at 'Crumb Rubber' near Dromiskin.
The explosion happened around 9.30am while a unit from Dundalk fire brigade were fighting a small fire which had started an hour earlier in the plant.
Two firefighters and two employees of the plant are in the specialist burns unit at St James' Hospital in Dublin in critical condition.
Three others, including two firefighters, are in a stable condition in Our Lady of Lourdes Hospital in Drogheda and will be kept in overnight.
The plant opened two years ago and is the only tyre recycling plant in Ireland. 36 people are employed at the plant, which contains €5 million worth of equipment.
Four units of the fire brigade were called to the fire. An official from the Health and Safey Authority attended the scene, while gardaí and the fire service are also investigating.
The cause of the blaze is not known, but it is thought to have been due to a problem with the aeration system.
