A New Zealand man last night told of fleeing his Port Vila office building when a 7.5 magnitude earthquake struck Vanuatu, sending frightened residents and tourists rushing for high ground.

Ben McKenzie, who has been working for the New Zealand High Commission in Vanuatu since October, said he ran from under a table to a doorway in his third-floor office as books fell from shelves around him.

The quake - which triggered a small tsunami of about 22cm and brought down power lines - struck about 40km northwest of Port Vila about 5.30pm (NZT) yesterday.

Early reports did not include any injured New Zealanders, High Commissioner Jeff Langley told the Herald last night.

Roland Cowles, manager of the Sunset Bungalows waterfront resort at Port Vila, said his wife Jenny suffered minor cuts as she fled a supermarket.

"For a good 10 seconds, you almost couldn't walk - it was throwing you around that much and people in the supermarket had to be evacuated because of all of the damage that was being done," he told Ten Network in Australia.

Police spokesman John Frat said officials had not received any reports of injuries or serious damage, but described the tremor as "a very sharp quake - the worst I have felt".

"Many people left the centre of town and went to higher places, fearing a tsunami," he said.

"We're still experiencing sharp aftershocks and all communications were lost for a time, but things are coming back to normal now."

Mr McKenzie, 31, from Wellington, said: "It was quite a big jolt, quite a long rolling quake. It would have lasted ... well, it certainly felt like it lasted ... for the best part of a minute and there were aftershocks.

"Fixtures on the walls came down, books and magazines and files came off the shelves, computers were tossed off their tables. It was very intense.

"Tiles were falling down and furniture falling over and bookshelves coming down."

Diplomatic staff were last night waiting for word of any New Zealanders caught by the shake.

High Commission staff said between 250 and 500 New Zealanders were believed to be in the country and they were checking to see they were all safe.

In Port Vila, foreign hotel guests and some residents raced to higher ground to avoid a tsunami, while police sounded warning sirens.

Mr McKenzie said that being a Kiwi, he knew exactly what to do when the quake struck.

"Having a good New Zealand school system education, I was under the table and then the doorway ..."

Up to six of the office's 18 staff were believed to be in the four-storey building when the quake struck at 4.30pm Vanuatu time. All were uninjured.

Then staff listened to the radio to find out about reports of damage.

Mr McKenzie, who is the commission's first secretary of development, was expecting to be called on for aid if needed.

But Mr Langley last night said no aid had been sought.

"We haven't got a very clear idea on how many New Zealanders might have been here temporarily as tourists - an average guess would be perhaps another couple of hundred.

"It was violent but it was over very quickly.

"There's been no reports from the officials that I've spoken to of any significant injury. There's been one or two reports of minor bumps and scrapes but no indication that any Kiwis are involved and at this stage there's no major reports of damage."

Mr Langley said general tsunami warnings had been issued by the Vanuatu and Pacific tsunami warning centres, but there had been no reports of tsunami damage.

Mr Langley said a structural engineer would inspect the commission's building today.

"We'll certainly need to do a bit of tidying up."

Mangoes resort owner Ros Cox said the only damage at her resort was "a bit of water sloshing into a couple of rooms from the pool".

There had been only mild panic from holidaymakers when the quake hit.

"They're all enjoying happy hour now," Ms Cox said.

- Additional reporting: NZPA