Three Australians and a New Zealander kidnapped in Nigeria have been released and are undergoing health checks, Foreign Minister Julie Bishop says.
The men worked for Perth-based mining company Macmahon Holdings and were among seven abducted after an attack by gunmen on the outskirts of the city of Calabar on Wednesday.
Macmahon said in a statement five of the group were injured, two seriously.
"I can confirm that all seven hostages have been released," Bishop told reporters on Monday.
Three Australian citizens and permanent resident of Australia from New Zealand, as well as the South African and the two Nigerians, were now safe, Bishop said.
"They are having health checks at present. It's obviously been a very traumatic experience for them," Bishop said.
A Nigerian driver was shot dead in the attack, while another Australian managed to flee.
Bishop said no ransom was paid for the men's release.
"That is because we do not want to increase the security risks for Australians travelling overseas," she said.
"It is a longstanding policy of Australian Governments, a bipartisan policy we do not pay ransom."
Arrangements have been made for the men's safe return to their families, once they receive medical clearance to travel, Macmahon CEO, Sy van Dyk said in a statement.
"Our men have been through a traumatic experience, and we have mobilised medical and other support teams in Nigeria to provide immediate support," he said.
"I also thank the men's families for working so closely with the company during what has been an extremely difficult time for them as well. They too have endured an incredibly stressful experience."