Gunmen <a href="https://en.wikipedia.org/wiki/2014_Kano_attack" id="mwAXw" rel="mw:WikiLink" title="2014 Kano attack">set off three bombs</a> at the central mosque in the northern Nigerian city of <a href="https://en.wikipedia.org/wiki/Kano_(city)" id="mwAX0" rel="mw:WikiLink" title="Kano (city)">Kano</a> killing at least 120 people.