LISTEN ABOVE: The Guardian's West Africa correspondent Ruth Maclean says kidnapped expatriates can fetch up to $1 million.

UPDATED 9.24PM: There's still been no contact from kidnappers in Nigeria who've taken a New Zealander hostage, along with three Australians, and a South African.

They're working for a mining company in an area of the country known for abductions.

Prime Minister John Key said today in a press conference that there was no chance of the government paying a ransom for Kiwi.

The Kiwi is also with at least two Australians, who were attacked on the outskirts of Calabar by gunmen who killed their driver.

Mr Key says it's likely the kidnappers want money, rather than being part of a terrorist organisation.

But he says our Government has a strong policy not to pay ransoms.

Mr Key says paying a ransom would put a bounty on the head of any New Zealander who travelled to a dangerous part of the world, and would potentially make the situation worse.

The Australian government is working with Nigerian officials to get to the bottom of the kidnapping.

NZH Focus: Latest on Kiwi kidnapped in Nigeria

Australian Prime Minister Malcolm Turnbull says the Australian high commissioner in Nigeria is at the scene.

The families of those kidnapped have been notified.

The trio are said to be contractors for cement company Lafarge Africa, Reuters reported.

The group were attacked on the outskirts of Calabar in the early morning (about 4.30pm yesterday, NZT).

A spokeswoman for Lafarge said its contractor in Nigeria, MacMahon, had alerted Lafarge Africa that a security incident had happened on the road from Calabar involving some of its employees.

The Australian mining giant MacMahon was working with government security agencies to resolve the situation.

The New Zealand Government confirmed a New Zealand citizen and a number of Australians working for an Australian mining company had been kidnapped.

The Nigerian Government said it was throwing everything it could behind the operation to secure the release of a New Zealand man, four other expats and two Nigerians.

The group was kidnapped after their driver was shot dead as he was taking them to work.

They all worked for the Australian mining and engineering company Macmahon.

Nigerian Government spokesman Christian Ita said security services, the police and army were doing everything possible to ensure the release of the New Zealander and everyone else affected.

They knew where the group was being held, he said.

Christian Ita said it appeared a militant group was responsible but he was unaware of any demands for money.

The Government was hopeful the hostages would be released soon.