Nigerian President Goodluck Jonathan has vowed to hunt down those behind "heinous" attacks which left at least 120 dead at the mosque of a top Islamic leader and vocal critic of Boko Haram.
At least 270 others were also wounded in Friday's attacks when two suicide bombers blew themselves up and gunmen opened fire during weekly prayers at the Grand Mosque in Kano, the biggest city in the mainly Muslim north of the country.
The president "directed the security agencies to launch a full-scale investigation and to leave no stone unturned until all agents of terror ... are tracked down and brought to justice," said a statement from Jonathan's office on Saturday.
"The president reaffirms that terrorism in all forms ... is a despicable and unjustifiable threat to our society."
He urged Nigerians "not to despair in this moment of great trial in our nation's history but to remain united to confront the common enemy."
The Grand Mosque is attached to the palace of the Emir of Kano Muhammad Sanusi II, Nigeria's second most senior Muslim cleric, who last week urged civilians to take up arms against Boko Haram.
The Emir was out of the country during the attack.
The blasts came after a bomb attack was foiled against a mosque in the northeastern city of Maiduguri earlier on Friday, five days after two female suicide bombers killed over 45 people in that city.
The special representative of the UN Secretary-General for West Africa, Mohamed Ibn Chambas, condemned the recent attacks in a statement.
Chambas called on the authorities "to increase their response against terrorist threats in north-eastern Nigeria" and for additional measures to protect civilians.
Observers have pointed the finger at Boko Haram for the attacks. Mass casualties are not a new phenomenon in the extremists five-year insurgency. More than 13,000 people are thought to have died in total since 2009.
