A series of aftershocks shook New Zealand on Monday, hours after a powerful earthquake killed two people.

Waves up to 6 feet high were seen near Kaikoura, a popular tourism area about 50 miles from the quake’s epicenter. The town is cut off after a highway and the main rail line were buried by landslides and has three more days of water left, the New Zealand Herald reported.

The country’s air force has started lifting 1,100 trapped tourists out of Kaikoura by helicopter, according to the New Zealand Herald.

It measured it as magnitude-7.5 and said it was the largest quake recorded in the country since 2009. The U.S. Geological Survey measured the quake as magnitude-7.8.

The tremors that followed included one that was magnitude-6.2, according to the U.S. Geological Survey. The aftershocks will continue for the next few months, the BBC reported.

People living near the Clarence River — one of the largest on the country's South Island — were urged to move to higher ground after the river breached its banks, according to the BBC.

The U.S. Geological Survey said the quake was centered less than 60 miles northeast of Christchurch, the scene of a devastating earthquake in 2011 that killed at least 185 people.

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