Emergency services are attending the scene of a serious crash involving a car and a truck at the intersection of Woodstock Road and Harmans Gorge Road, Waimakariri.

Police were called to the scene about 11.40am.

Initial reports indicate one person is critically injured, and another person is understood to be seriously injured.

The Serious Crash Unit has been advised.

The road is expected to be closed for some time, with diversions being put in place.

Motorists are advised to avoid the area.

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