A man is missing on the West Coast after being swept away while trying to cross a tributary of the Grey River in a four-wheel-drive.
Police said they were alerted at 11.30am this morning and have since been searching the remote Ikamatua area.
A police spokesperson, Barbara Dunn, told Radio New Zealand News this afternoon that a large team of searchers was involved.
"We've got a jetboat on the river and we've got a whitewater rescue team, which is five kayakers on the river. A helicopter has been searching from the air. We've got some ground crews in there but the job is pretty difficult for them because of the terrain."
Ms Dunn said the search has also been hampered by the rain, which has swollen the river.
The search for the man has now been called off for the night, with police saying they are yet to find any trace of him.
They said the situation would be reassessed in the morning.
They said they had still not spoken to the people travelling with the man to work out exactly what happened before he disappeared.