Two expats have been kidnapped at an oil rig in the Nigerian delta, according to reports.
A British worker and a Canadian worker are believed to have been taken by armed gunmen at 8am on Saturday.
The incident took place at a rig in Ogbele, Rivers State, which was owned by local oil drilling firm.
The abduction is the second there in less than a week.
On Thursday, two Royal Dutch Shell oil workers were kidnapped and their police escorts killed while returning from a trip.
Major Ibrahim Abubakar of Operation Delta Safe said: ”At about 8am on April 27, some gunmen visited the rig belonging to Niger Delta Petroleum Resources and carried out the attack and kidnapped two expatriates.
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”When we heard about the incident, we mobilised to comb the swamp but to no avail; we couldn't arrest the perpetrators.
"Efforts have been intensified to rescue and arrest culprits, but we have also advised the management to provide adequate security to their operations."
The Niger Delta produces the bulk of Nigeria's crude.
It has been plagued by criminal gangs and by armed groups demanding a greater share of oil revenues.
The Foreign and Commonwealth Office has been approached for comment.
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In 2017, a British charity worker was killed by militants in Nigeria after being taken hostage.
Ian Squire, an optician from Surrey was doing charity work in the oil-rich Delta region.
The other three who were kidnapped, Alanna Carson, David Donovan and Shirley Donovan, were released.
Earlier this month gunmen killed a British woman as well as abducting three others.
Faye Mooney had traveled from Lagos to the northern city of Kaduna as a tourist and was attending a party before the incident happened, police said.
While the British High Commission released the woman's name and confirmed it was aware of the incident, it refused to speculate on the motive or nature of the attack.
No one has claimed responsibility for the incident and the kidnappers have yet to be identified, police said.
Tributes to the Briton were led by Neal Keny-Guyer, chief executive of Mercy Corps, an American NGO which provides humanitarian aid to 38 countries.
He said: "Faye was a dedicated and passionate communications and learning specialist who had worked with Mercy Corps for almost two years, devoting her time to making a difference in Nigeria, supporting our teams and the communities we work with to tell their stories of impact, and leading efforts to counter hate speech and violence.
