Retaurants closed by health officials inspecting gas appliances

The owners of the Ice House restaurant in Portstewart and a chip shop in Rasharkin pulled down the shutters as inspectors continued to question the gas fitter who installed the heater suspected of killing 18-year-old school pals Aaron Davidson and Neil McFerran in Castlerock.

It is understood the proprietors of both businesses contacted the Health and Safety Executive (HSENI) – two of nearly 500 people to ring an emergency helpline since it was set up on Monday.

When asked about the restaurant closures, a spokeswoman from HSENI said: "HSENI and gas supply companies have been active in the Castlerock and Coleraine areas to make safe a number of homes and premises as part of their ongoing emergency response."

The development came as Stormont ministers prepare to meet today to discuss whether carbon monoxide detectors should be compulsory in new builds in the province.

The HSENI found that a liquefied petroleum gas (LPG) appliance inside a flat at Tunnel Brae Court had not been working properly.

The heater was fitted by the Calor Shop in Coleraine, which is run by George Brown.

All businesses and householders who had their appliances fitted by Mr Brown had subsequently been urged to switch off their supply and call the HSENI.

Earlier Mr Brown passed his condolences to the teenagers' families and pledged his cooperation with investigators.

The Calor Shop run by Mr Brown is an entirely separate legal entity to Calor Gas (NI) Limited.