A search and rescue operation was under way near Arthurs Pass last night for a tourist.

The woman, believed to be in her 50s and from Britain, had been tramping in the area, police said.

She may have been missing for days but her disappearance was not discovered until yesterday afternoon.

Her pack was found on the Mt Aicken track at a height of about 1700m.

Meanwhile, a body found in bush on the West Coast on Saturday afternoon was that of missing Japanese tramper Katsusbaro Nagashima.

A white-water rescue team found the body caught in a logjam in the Fox River just before dusk.