Over the weekend, a woman suicide bomber blew herself up at a crowded evangelical Christian church in the northeastern city of Potiskum, killing six people.
The restaurant destroyed by another explosion is said to have been popular among state governors and other top politicians.
Christians and Muslims in the city of Jos, Nigeria were killed in a string of recent attacks by a militant group.
The city of Jos has endured several attacks attributed to Boko Haram, including an incident in February that killed at least 15 and one in December 2014 which saw more than 30 deaths.
“El-Rufai, who suspended government activities to travel to Zaria on Tuesday, said:” I am sad that a terrorist bomb attack just killed 20 people in Sabongari, Zaria.
Some 32 churches and about 300 homes were torched during that time, according to the chair of a self-defense group in Borno state, Stephen Apagu.
Nigerian President Muhammadu Buhari has sworn to end the Boko Haram insurgency, which has escalated its attacks recently.
Buhari said on Sunday that Boko Haram, which has allied itself to the Islamic State group in Syria and Iraq, had “declared war on all that we value”.
“A young lady wearing a veil with explosive devices strapped at her body detonated an IED at a checkpoint… before she was checked”, the military source said.
The attack came hours after a suicide bomb attack at a Mosque in Kano on Monday.
Ado Aliyu, a survivor who was shot in the arm, told CNN that about five gunmen entered the crowd and started shooting, setting off a stampede before the explosion struck.
Shares of the Global X MSCI Nigeria ETF (NGE) are down almost 2% after a Boko Haram terror attack resulted in more than scores dead.
A report last month by Amnesty global says that Nigeria’s tactics against Boko Haram have also proven deadly to the country’s citizens as well.
On Friday, Chadian security officials said they had seized a large weapons cache, including rockets, in a house in N’Djamena. He said the militia killed three militants.
A statement from the president’s office on Sunday quoted him as condemning the resumption of attacks by terrorists on places of worship which are highly revered places of prayer and communion with God for most Nigerians.