At least 29 people were injured by the explosion which rocked the Chelsea neighbourhood of Manhattan, New York, Saturday night.
The blast, believed to be a terrorist act, was suspected to have come from a homemade improvised device.
The New York Times reported that Mayor Bill de Blasio, who described the incident as “an intentional act”, said “Whatever the cause, New Yorkers will not be intimidated”.
A second device was said to have been found while no suspect was arrested immediately. But police authorities vowed to get to the root of the matter.
New York City is host of a UN meeting and Nigeria’s President Muhammadu Buhari is scheduled to address the UN Assembly.