The former governor of one of Nigeria’s richest oil-producing states was jailed for 13 years in the UK today after admitting fraud totalling nearly £50 million.

Militants in Nigeria today released their last remaining foreign hostages, setting free two American oil-industry workers and one Briton after more than five weeks in captivity.

Nigerian militants have released six foreign oil workers they deemed “low value”, but held on to two Americans and one Briton and threatened crippling new attacks aimed at cutting off all oil production in Nigeria.

Officials in an oil-rich southern Nigeria state where militants took nine foreigners hostage, including a British man, were today investigating conflicting reports that three of the captives had been released on medical grounds.