A Christchurch surfer caught up in yesterday's cliff collapse at Sumner says he and a friend paddled for their lives as rocks the size of cars crashed into the ocean.
Scottie Behrnes and his friend were just metres from the cliff when the 5.7 magnitude quake struck.
He says they're lucky to be alive.
"All of a sudden the cliff just came right down on top of us and we just went 'shit' and paddled for our lives," says Mr Behrnes. "Big rocks the size of cars were landing all around us – you were just waiting for an impact on your back, you weren't sure if it was going to hit you."
He says they were only around 20 metres away from certain death.
"I just remember looking up and it looked like the whole cliff was shearing off, just a big dust cloud and huge boulders pouring down and it felt like they were right above us. We just dived on our boards and paddled as far offshore as we could and waited for things to hit us."
Other surfers at Sumner caught the collapse on their phones and shared footage on social media.
The city was rocked by a series of aftershocks overnight, the most powerful of which was a 3.9 magnitude tremor which struck just after 8:30pm.
Civil Defence Minister Nikki Kaye said she was happy with the response to the quake yesterday.
"Civil Defence was mobilised, the National Crisis Management Centre has been activated, but that's really just to coordinate -- there are no major reports of injuries, we are obviously activated just in case there is structural damage."
She is reminding people to drop, cover and hold in the event of more aftershocks.