nigeria troops
Attacks across Nigeria killed at least 20 people on Sunday. In this photo, soldiers are seen on a truck in Maiduguri in Borno State, Nigeria May 14, 2015. Reuters

Update as of 2:54 a.m.: The death toll from two bombs that exploded Sunday night at a mosque and a restaurant -- in the central Nigerian city of Jos -- had risen to at least 44, while 67 others were injured, according to the Associated Press.

Original story:

Suicide bombings and bomb attacks killed at least 20 people in Nigeria on Sunday, according to media reports. Nobody has claimed responsibility for the attacks, but the method is reportedly consistent with previous bombings carried out by the extremist Boko Haram group.

A suicide bomber blew himself up in the Redeemed Christian Church of God in the town of Potiskum in northeastern Nigeria, killing at least 5 people including the priest, CNN reported. Potiskum has been the target of at least four such attacks by militants this year, which have focused on schools, government buildings and transportation hubs as well as churches.

Two bomb blasts also struck the central city of Jos, one near a mosque and another in a Muslim-majority neighborhood. CNN reported that at least 15 people were killed and 20 injured in these attacks.

Since coming to power in May, Nigerian President Muhammadu Buhari has made tackling the militant group a national priority, calling for major increases in security funding and bolstering the military campaign against the group in the country’s northeast.

The previous administration of former president Goodluck Jonathan was condemned for failing to prevent Boko Haram’s rise, despite spending billions of dollars on national security.

Fresh concerns were raised in March when the militant group, which is also active in neighboring countries including Niger and Cameroon, pledged allegiance to the Islamic State group.

Meanwhile, Washington also condemned Boko Haram’s ongoing violence and vowed greater support to Nigeria. "As we have said before, the people of northern Nigeria deserve to live free from violence and from terror. The United States continues to provide counterterrorism assistance to help Nigerian authorities develop a comprehensive approach to combat the threat posed by Boko Haram," State Department spokesman John Kirby said in a statement.