Some residents and people of Anambra State have condemned the killing of worshippers early on Sunday morning at St. Philips Catholic Church in Ozubulu community of the State.
On getting to the church, he had left and out of anger, probably, they rained bullets on worshippers in the church.
Earlier, the Parish Priest of St. Philip's Catholic Church, Rev. Fr. Jude Onwuaso, said the attack took place at about 6.30 a.m. during Mass.
According to the President, there is no religion that does not lay constant emphasis on the sanctity of life, and that "all Nigerians must rise up and speak with one voice against these remorseless evil men".
He extended his heartfelt condolences to families of the victims, people and government of Anambra state, Nigeria and the Catholic Church over the sad and unfortunate incident.
Speaking in an interview with TVC News, the Commissioner of Police, Anambra State Command, Garba Umar said the eleven worshippers were shot dead by the gunmen after they missed their target whom they had traced to the Church.
Three shot at San Francisco park crowded with families
When asked if the incident appeared to be gang-related, she said, "It does not appear that this is a random event". Witnesses say the park was packed at the time of the shooting with families and tourists who ran seeking cover.
Garba linked the attack to a lone gunman who he said spoke local Igbo dialect.
"So far, 12 persons have been confirmed dead and deposited in the mortuary here while several persons are receiving medical attention", said a staff worker at Nnamdi Azikiwe University Teaching Hospital in Nnewi, where the victims were admitted.
Governor Willie Obiano has however vowed not to rest until the perpetrators of the killing are brought to justice.
That man was shot and then a rampage ensued, with indiscriminate fire directed at the roughly 100 worshippers on hand.
Security agents were said to have cordoned off the church.
The police commissioner said the fact the violence erupted in a church makes it especially heinous, saying, "Such conduct shows the people behind the act do not fear God".