A helicopter with a winch is on its way to Milford Sound, after a person fell into water and could not get out.
The person was walking on the Chasm walk when they fell about 6m into water, about 1.40pm, Senior Sergeant Ben Butterfield, of Dunedin, said.
The person was uninjured and made it to shore, but could not get themselves out of the area.
Fellow walkers were able to raise the alarm, with police and a helicopter with winch heading to the scene.
