At least two people are confirmed dead after a series of powerful earthquakes struck New Zealand early on Monday (local time). The tsunami triggered by the temblor forced thousands to flee their homes seeking higher, safer ground.

Railway lines and roads have been rendered unusable as they are either blocked or severely damaged. The New Zealand Transport Agency said they were ”working urgently” with the police, KiwiRail and local authorities to coordinate efforts to transport people out of closed localities. A state of emergency has been declared in tourist hotspot Kaikoura, though no serious injuries were reported from the town.

Authorities had expected the tsunami activity to continue for hours, but they lifted the initial warning in the afternoon (local time). New Zealanders, however, have been advised to steer clear of the water because of strong currents. Severe weather warnings are in place, which officials fear will hinder rescue efforts. Prime Minister John Key is touring affected regions by helicopter to take stock of the damage.

The first quake, which was recorded at 7.5 magnitude on the Richter scale, hit around 95 km from Christchurch. It was followed by several aftershocks, some measuring as high as 6 on the scale. The first waves arrived in the north-eastern coast two hours after the quake.

According to The Guardian’s correspondent in Australia, Michael Slezak, the epicentre of the earthquake was at the boundary between the Pacific tectonic plate, where most of New Zealand’s South Island lies, and the Australian plate, where only the northern part of the island lies.

The last major earthquake to hit the country was in 2011, when 185 people were killed and thousands injured in a 6.3-magnitude quake that affected Christchurch the worst.