In April's election Mr Jonathan won a majority of votes in the south only, where he is from. He is not known as a divisive figure but inspires little confidence outside his core supporters. He has yet to announce his new cabinet and Sunday's blast underlines the importance of bringing prominent and credible northerners into the government to bridge the growing chasm between the mainly Christian regions along the Gulf of Guinea and the predominantly Muslim population that borders the northern Sahel states.

The election further deepened the long-running ethnic and religious divide that runs through the country. More than 800 people died in the week after the poll as disappointed voters and hired thugs rampaged through northern states, including Bauchi.

Cynics have said that it is a sign of progress in Nigeria—where vote-rigging is rampant—that most of the violence now occurs after the poll, rather than before, as used to happen. That means voters see the polls as credible enough to feel disappointed. But to stand a chance of avoiding violence in the future, Mr Jonathan will have to make his government truly representative.