LATEST: Foreign Minister Julie Bishop has confirmed that two Australians have been taken by armed militants.
She has told Australian media that the Australians were thought to be travelling in a convoy when they came under attack on Wednesday morning local time.
The Australian Government is in close contact with the Nigerian government, which she said were taking the abduction extremely seriously.
The ABC reports the workers are understood to be employed by Australian engineering firm Macmahon.
A New Zealander, South African and two Nigerians are also understood to have been taken.
ABC News reports Nigerian police commissioner Jimoh Ozi-Obeh said police was working with the Nigerian Navy to have all victims released unharmed.
"The police are aware of the matter. Five persons were kidnapped," he said.
"They include two Australians, one South African and two Nigerians. The driver of the vehicle was shot dead."
No ransom demand has been received.
EARLIER: Two Australians, Kiwi kidnapped by gunmen in Nigeria
TWO Australians and a New Zealander have been kidnapped in southern Nigeria by gunmen who killed their local driver.
The trio are said to be contractors for cement company Lafarge Africa, Reuters reported.
There are conflicting reports about the victims but local newspaper, The Punch, said it was understood that at least five foreign workers were caught up in the attack - including three Australian men, one South African national and a man from New Zealand.
Two Nigerian workers were also kidnapped.
A source told the publication the men were being driven to their workplace in four vehicles and escorted by security - when they were attacked.
One driver was killed in the attack.
The group were attacked on the outskirts of Calabar in the early morning (about 4.30pm yesterday, NZT).
A witness told The Punch he was returning from his farm yesterday when he saw the incident occur just before the Idundu Bridge, in the eastern part of of the city of Calabar.
"These kidnappers came out from the bridge, shot the driver of the vehicle and took the victims away through the river.
"The vehicles conveying the expatriates and the two Nigerians were abandoned by the road-side with the dead body of the driver. From all indications, the expatriates were going to work at the Lafarge Holcim plant in Mfamosing.''
A police spokeswoman for Cross River state Police told the publication two of the men had since managed to escape - but she did not know the nationality of those workers.
The kidnappers are yet to make contact with police.
More to come.
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