Search and rescue teams are searching for a person who has gone missing at a waterfall in the South Island.

A police spokesperson said another person was earlier pulled from the water.

Emergency services responded to the incident at Maruia Falls in Shenandoah, near Murchison.

"About 12.10pm one person was pulled from the water. However, a second person is still outstanding," the police spokesperson said.

A rescue helicopter is on its way to the waterfall and Search and Rescue staff have been notified of the incident.