A gas fitter whose business is being investigatated over the deaths of two teenagers has expressed his sympathy to their families.
Calor Shop owner, George Brown, said he will co-operate with the authorities.
His shop in Coleraine was searched by police and the Health and Safety Executive (HSENI) investigating the suspected carbon monoxide leak.
Aaron Davidson and Neil McFerran, both 18, died in the holiday apartment in Castlerock last Tuesday.
The HSENI has advised anyone who has a gas appliance fitted by Mr Brown's business, the Calor Shop in Coleraine, to switch it off.
A solicitor for Mr Brown relased the statement on Wednesday morning.
"Mr Brown would like to express his most sincere condolences to the Davidson and McFerran families following their tragic loss.
"Mr Brown fully supports the investigation being carried out by the authorities.
"He will help and co-operate to the fullest possible extent, and in any way possible, in order to assist the investigation into this tragedy.
"He has been in constant contact with the authorities since the tragic events have occurred.
"He thanks all those friends and customers who have contacted him offering messages of support, but would ask that all thoughts and prayers be with the Davidson and McFerran families at this time."
The Calor Shop run by Mr Brown is an entirely separate legal entity to Calor Gas (NI) Limited.
The premises was searched by the authorities on Tuesday night.
Aaron and Neil, from Newtownabbey outside Belfast, had been spending time at the apartment awaiting their exam results when they were overcome by poisonous fumes last week.
A third teenager, Matthew McGaw, also 18, survived the leak.
The HSENI found that a liquefied petroleum gas appliance inside a flat at Tunnel Brae Court had not been working properly.
On Tuesday night, the HSENI investigated reports of another suspected carbon monoxide leak in the area.
It is understood two women who worked at a building in the Portmore Road area of Portstewart contacted doctors after feeling unwell.
Following blood tests it was determined they did not have carbon monoxide.
The owners of the building said it was "100% safe".
Meanwhile, the Finance Minister Sammy Wilson has said he will look at the possibility of making carbon monoxide alarms compulsory for all newly built homes.
Mr Wilson will meet the minister responsible for health and safety, Arlene Foster, on Thursday to discuss the matter.