A fourth person has died after a crash near Lake Pukaki.

The crash between two vehicles and a motorcycle happened between Hayman Road and Tekapo Canal Road on Saturday.

Three people died at the scene, two of whom were foreign students from Malaysia.

Another three were airlifted to hospital in a serious condition and two people had moderate injuries.

Police said the fourth person to die was one of those in a serious condition.

They died from injuries overnight.

Police were investigating the crash and working on formally identifying those who died at the scene.

They spoke to several people present at the scene following the crash, but are asking for witnesses to come forward "in order to build a complete picture of what occurred".

Anyone with information is asked to contact police on 105 or report online, quoting file number 240331/4655.

The death takes the Easter weekend road toll to seven.

On Sunday, the Malaysian government confirmed five Malaysian students were involved in the crash.

"The ministry and High Commission of Malaysia stand ready to assist should the next-of-kin decide to repatriate the remains to Malaysia."

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