An international Christian ministry that assists persecuted members of the faith says hundreds of Christians have been killed in a series of attacks in Nigeria.

This is the African nation where members of the Muslim jihadist group Boko Haram earlier vowed to "eradicate Christianity."

At the time of the threats just weeks ago, the Nigerian news site Bikya Masr reported the group had declared war on all Christians living in northern Nigeria.

Human-rights group International Christian Concern's Jonathan Racho called the news alarming.

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Now the Barnabas Fund is reporting that some 300 Christians were killed in one diocese alone, and 27 people died in attacks on three church services as recently as Sunday.

"The first happened when people had gathered for worship in two lecture theaters at Bayero University in Kano. So far 22 people are confirmed to have died, while 23 were injured, after bombs were thrown into the building at around 8.30 a.m. and gunmen fired on worshipers. Witnesses said that the offenders first threw in explosives and fired shots, and as Christians fled, the gunmen chased them, firing indiscriminately," the organization reported.

"Later on Sunday, gunmen opened fire on another church in the northeastern city of Maiduguri. Five people, including a pastor, were killed in the attack at the Church of Christ in Nigeria building."

Barnabas Fund said the claims for responsibility, which sometimes take time to develop, had not yet come in, but most people suspect Boko Haram.

Other Nigerian violence was reported on Easter Sunday, when in Kaduna 40 were killed in a suicide bombing outside two churches. Later, in Jos, another attack left a pregnant woman and an 18-month-old child among those killed.

"The simple act of going to church on a Sunday has become a perilous one for Christians in many parts of Nigeria," said Patrick Sookhdeo, international director for Barnabas Fund. "They very much need our prayers as they courageously continue to gather for worship despite the unrelenting violence."

Racho reported weeks ago that Boko Haram announced it would "launch a number of attacks targeting Christians."

He said the goal is "eradicating Christians."

"We are very outraged. How can a country like Nigeria with all of its resources, its oil resources, security, military and all the resources ... fail to protect its innocents from these kinds of attacks?" Racho said at the time.

Violence also has developed against Christians in Kenya, where a band of Muslims recently launched a grenade attack against 150 Christians attending an open-air meeting.

WND also reported in December that a Christian man in Kenya was beaten by a Somali mob that crossed the border for the attack.