Update: Three lives lost in Redwood Pass crash

Police confirmed a third person died following Sunday's crash on SH1 near Redwood Pass.

Two people died at the scene, NZ Police said, and three others were transported to hospital with serious to critical injuries.

"Sadly, despite best efforts by medical professionals, a third person has since passed away," police reported on Monday. "The two other injured remain in hospital in a serious and critical condition."

Emergency services responded to the two-vehicle crash in Marlborough at around 10:40am on Sunday. SH1 was closed about six hours as the Serious Crash Unit conducted a scene examination.

The road has since reopened. Police said the investigation "into the circumstances of the crash remain ongoing".