New Zealand ? A flotilla of hundreds of icebergs that split off Antarctic ice shelves is drifting toward New Zealand and could pose a risk to ships in the south Pacific Ocean, officials said Tuesday.

The nearest one, measuring about 100 feet tall, was 160 miles southeast of New Zealand’s Stewart Island, Australian glaciologist Neal Young said. He couldn’t say how many icebergs in total were roaming the Pacific, but he counted 130 in one satellite image alone and 100 in another.

Large numbers of icebergs last floated close to New Zealand in 2006, when some were visible from the coastline — the first such sighting since 1931.

Maritime officials have issued navigation warnings for the area south of the country.