Priests are vulnerable to kidnapping for several reasons, Uganwa said. They are often a visible and well-known member of a community; they rarely carry weapons; and often are found in predictable places, such as their rectory or church.
The Nigerian bishops' conference last year announced that the diocese ought not pay ransom for a priest's release, so oftentimes well-meaning parishioners will pool together their money to get their priest back.
"By and large, no priest comes out of captivity without ransom being paid," Uganwa told CNA.
In a high-profile kidnapping case from earlier this year, gunmen abducted four seminarians from Good Shepherd Seminary in Kaduna, holding them for random. The kidnappers eventually released three of the seminarians, but killed 18-year-old Michael Nnadi after he refused to renounce his faith.
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In the northern part of the country, Fulanis often clash with Christians in land disputes. The radical Islamist group Boko Haram, which emerged around 2009, is still active and has carried out devastating terror attacks on Christians in recent years.
Such incidents include attacks in late July on four Christian villages in southern Kaduna, in which more than 62 Christians were killed by Islamic terrorists. Also in July, an Islamic extremist group boasted of killing five international aid workers, three of whom were known employees of Christian aid agencies.
Boko Haram is affiliated with the Islamic State, and to date has displaced more than 2 million people from their homes. The name Boko Haram roughly translates to: "Western education is forbidden."
Father Joseph Bature, a priest of the Diocese of Maidugui, told CNA in August that he estimates that since 2009, Boko Haram has driven out half of the 300,000 Catholics who used to live in the diocese. The region around Maiduguri is where Boko Haram first emerged.
Though Catholics there still celebrate Mass openly, they have to take stringent security measures against suicide bombers.
"Boko Haram is still very active, not in the city so much [as] in the outskirts...They still do the kidnapping, they still do the bombing. They still set mines on the road," Bature said.
The problem of internally displaced persons, mostly Christians who have been driven from their homes, is especially acute in the north, where thousands of the destitute live in refugee camps.
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"Around here, around Maiduguri, over 1.2 million are displaced. About 1.4 million, and the number keeps rising on a daily basis. [In] the entire country, you have over 2.4 million people internally displaced. Now that's quite huge," Bature said.
Part of the problem, Nigerian Christians have told CNA, is that the Muslim-dominated government has largely responded slowly, inadequately, or not at all to the problem of Christian persecution.
"The most important issue is that unfortunately, the government in Nigeria does not show enough will, either in speech or in action, to help to curb the violence and the bloodshed that we see, either from the terrorists or from bandits or from a headsman, because we have so many sorts of groups running riots all over the Northeast of Nigeria," Bishop Emmanuel Badejo of Oyo told CNA.
Bishop Badejo said although his diocese is more peaceful than some in the north, with Muslims and Christians largely co-existing peacefully, there are some means of persecution that are more systemic and subtle, with government appointments and written laws seeming to favor Islam over Christianity.
"It's no secret that in Nigeria, especially with the Buhari government, there are all written laws that have not favored Christians at all, that have favored, in other words, the Muslims," Badejo said, noting that Buhari is himself of Fulani ancestry.
"The Christian Churches have protested, Christian leaders have protested, but the federal government has not said any word in order to show any desire to protect the Christian religion."