Firefighters were called to the container – at New Herrington Industrial Estate, Houghton – at around 8.30am on Wednesday, July 29 and spent four hours fighting the blaze.
Crews from Farringdon station attended the scene, before being relieved by colleagues from Washington and Sunderland Central.
Two breathing apparatus, one hose reel and special Cobra Cold Cutting equipment were used to bring the fire under control.
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Crew manager Chris Kelly told the Echo at the scene that firefighters were working to dampen down hotspots within the container – which was ‘packed full’ of cardboard and wicker coffins – to ensure the blaze did not reignite.
A spokeswoman for the North East Ambulance Service also confirmed that one patient was taken to Sunderland Royal Hospital with ‘injuries consistent with burns and smoke inhalation’.