A small child, a man and woman have been treated for breathing in smoke after a fire at a house in Coleraine, County Londonderry.
The blaze at Ballycastle Road was reported to Police around four o'clock on Sunday morning.
It caused substantial damage to the property.
The occupants and neighbours had to be evacuated.
John Beacon from the Northern Ireland Fire and Rescue Service says the fire started at the rear of a property.
''On arrival fire crews discovered the oil tank engulfed in a large fire.
''Five fire appliances attended the scene, One from Coleraine, Two from Portrush, One from Portstewart and One from Ballymoney.
''The fire and emergency support unit were also sent to the scene. Fire crews worked quickly to ensure the fire did not spread to adjoining properties and contained the scene very quickly ensuring the safety of all residents nearby.''
PSNI Chief Inspector Mark McClarence appealed for information.
''The cause of the fire has yet to be established, however, I would appeal to anyone who was in the Ballycastle Road area at around 4am this morning and who may have information which could assist with police enquiries, to contact officers in Coleraine on 101.''
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