At least 23 people have been killed and 108 injured in a series of suspected suicide bombings in Maiduguri, the capital of Nigeria's north-eastern Borno state, police say. A post office, a popular weekly market, and the University of Maiduguri Teaching Hospital were hit within minutes of each other at around 19:30 local time (18:30 GMT) on Monday, locations that had drawn large crowds after the day's Ramadan fast was broken. Monday's explosions represent one of the deadliest attacks Maiduguri had witnessed in years. The city was once the epicentre of an insurgency by militant Islamist group Boko Haram but had been enjoying a relatively stable period. Preliminary investigations suggest the incidents were carried out by suspected suicide bombers, with investigations ongoing to identify the attackers. Witness reports from residents describe a sudden loud explosion that sent people fleeing in panic. Nigerian President Bola Tinubu condemned the attacks, asserting that the culprits would be confronted and defeated. Security forces had just repelled an overnight assault on a military post before these incidents, highlighting ongoing threats in the region.