The violence in Nigeria continues as 15 people are expected dead after a homemade bomb exploded in the northeastern city of Maiduguri's main marketplace.

The blast occurred at 8 a.m. local time in a busy traffic circle as business was beginning to pick up for the day. The victims appeared to be mainly elderly women and poor, young boys, according to a local vigilante battling the Boko Haram, according to CNN.

Conflicting reports make it unclear whether the blast was a suicide bomb or a car bomb; however, witnesses and paramedics say it is the most recent attack by Boko Haram, an Islamic extremist group that has been terrorizing northeastern Nigerian villages.

Boko Haram attacks generally follow the same pattern: a “two-pronged strategy this year of bombings in urban areas and scorched-earth attacks in north-eastern villages, where people have been gunned down and their homes burned,” the Guardian reported.

This is only the most recent attack in Boko Haram’s siege of Nigeria’s northeast. The group gained international attention with the kidnapping of over 200 schoolgirls in April; however, reports say the extremists have been terrorizing locals since 2002.