According to a statement by his spokesman, Guterres “reiterated UN's support to the Government of Nigeria in its fight against terrorism and violent extremism.”

“[He] hopes that those responsible for this act will be swiftly brought to justice,” the statement added.

In the statement, Guterres also offered his condolences to the families of the victims, the people and the Government of Nigeria as well as wished a quick recovery to those injured.

According to reports, at least nine people were killed and another 13 were injured when suicide bombers struck locations across the city on 25 and 26 June.

Borno state, in northeast Nigeria has been plagued by violent attacks carried out by the Boko Haram terrorist group, and Maiduguri (the state capital) has been targeted many times.