The Home Office is not confirming or denying whether any British workers have been involved.
But officials say they are investigating reports which suggest at least one Briton was taken when gunmen stormed a compound belonging to a Lebanese construction company in Nigeria.
ITV News reporter Sejal Karia talks from outside the Foreign Office:
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Airstrikes were launched into Syria and tanks reportedly sent in as Turkey targets militants threatening its border.
Owen Smith has pledged to block formal Brexit negotiations until the government offers a second referendum or calls a general election.
The former pin up said she couldn't open her eye for about four hours - but the scenes have been cut from the show.