The Northern Ireland Ambulance Service is examining eight incidents of delayed response where deaths are involved.
Four, so far, are being treated as Serious Adverse Incidents, while the remaining four are still being considered.
The first five of the eight incidents were identified between December 12 – 22.
A NIAS spokesperson said the incidents involved were where a response was delayed to a patient, in line with the categorisation of the call, and where a death was involved.
A spokesperson said each incident was reviewed, by a NIAS internal Rapid Review Group (RRG), to determine if the incident should be notified as a Serious Adverse Incident (SAI).
“Four of the five incidents have subsequently been notified as SAIs,” they said.
“The fifth incident required further detail and will be reviewed on January 5, when a determination will be made as to whether it should be notified as a SAI.”
Since December 24, a further three incidents have been referred to the RRG for consideration to determine if they should be notified as Serious Adverse Incidents.
“These incidents will be considered on January 5,” the spokesperson added.
Ambulance have been under severe pressure in recent months, with scores having to wait for many hours outside hospitals before patients can be admitted in a knock-on impact of pressure on health services.
Last month it emerged a patient waited four-and-a-half days for treatment at an emergency department in a Northern Ireland hospital.
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