Thirty-five people were killed and 150 injured when multiple explosions tore through the central mosque in Kano, police said.
The survivors had various degrees of injury in the Friday blasts in Nigeria's second-largest city, State Deputy Police Commissioner Sanusi Lemu said.
Hundreds had gathered to listen to a sermon in a region terrorised by attacks from the militant group Boko Haram.
Witnesses said heavy smoke could be seen billowing in the sky from far away. Immediately after the blasts, hundreds of angry youths took to the streets in riots, throwing stones, brandishing sticks and shouting at security officials.
Boko Haram has not claimed responsibility, but the attack bears the hallmarks of the militant group that has made numerous such attacks in northern Nigeria, including in Kano. In September, two suicide bombers killed at least 15 students at a government college and in July, five suicide bombings occurred in a week. More than 1500 have been killed this year in the insurgency.
UN Secretary-General Ban Ki-moon called the attack horrific, pledged UN support for Nigeria's fight against terrorism, and called for the perpetrators to be swiftly brought to justice.
Nigerian President Goodluck Ebele Jonathan condemned the attack and reiterated the Government's determination to "continue to take every step to put an end to the reprehensible acts of all groups and persons involved in acts of terrorism".
He called on all Nigerians "to remain united to confront the common enemy" by being vigilant and co-operating with security agencies. He also called on relief agencies and medical staff to "deploy every possible effort to assist the injured" and urged the public to donate blood to the hospitals where they are treated.
Meanwhile, a police anti-bomb squad defused six bombs planted near a mosque and a market in the northeastern city of Maiduguri on Friday.
- AP