Gunmen in southern Nigeria have killed a local driver and kidnapped two Nigerians, three Australians, a New Zealander and a South African working for an Australian mining company, officials said.
The abduction happened in the Akpabuyo district near the capital of Cross River state, Calabar, at about 7am on Wednesday, Nigerian police said on Thursday.
Those taken were believed to be workers with Australian mining and engineering giant Macmahon, which was contracted to cement company LafargeHolcim in the state, police commissioner Jimoh Ozi-Obeh told reporters.
"The police is currently working with the Nigerian Navy to ensure that the victims are released unharmed," he added.
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Australian Prime Minister Malcolm Turnbull said they are working with Nigerian authorities to free their citizens.
"We are working with the authorities, local authorities, at the highest levels," Turnbull told reporters in Geelong, Australia.
"We don't know at this stage the identity of the kidnappers and families in Australia are notified, of course.
"It is a very serious kidnapping, a very serious criminal assault, one person was killed and seven people have been kidnapped."
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Irene Ugbo, a spokeswoman for Cross River state police, said no ransom demand had been received.
One witness to the abduction, who asked not to be identified, said the kidnappers took the men to a waiting boat.
LafargeHolcim spokeswoman Viola Graham-Douglas said the company was informed of the incident by Macmahon, which was "working with the security agencies to resolve the situation".
Macmahon has an $18m a year contract with the United Cement Company of Nigeria Ltd (UniCem) for quarrying operations at UniCem's cement manufacturing plant at Mfamosing, near Calabar.
UniCem is a joint venture between Franco-Swiss conglomerate LafargeHolcim and Flour Mills of Nigeria, according to the Australian firm's website.
Kidnapping for ransom has been a long-standing problem in southern Nigeria, particularly in the oil-producing delta region, where criminal gangs target wealthy Nigerians and expatriate workers.
Most are usually released after the payment of a ransom.