A government spokesman has said Abuja residents should remain calm tonight, saying that security agencies are now "handling the situation."
The latest explosion in Nigeria's capital, Abuja, killed 21 and injured 17 people in a shopping complex.
Spokesman Mike Omeri told AP: "Every step is being taken by the government to check the activities of insurgents in the country."
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The hospital was last attacked just three days ago, something that UN Secretary General Ban Ki Moon denounced as a war crime.
Former UKIP leader Nigel Farage has flown to the US to help coach presidential candidate Donald Trump ahead of his next debate.