He intimated the worshippers on the true picture of the incident, saying there was nothing to worry about.
The attackers then went to the church to hunt for him, but could not find the intended target and became angry, he said.
According to her, the gunman, after the shooting, immediately jumped into a waiting auto with a driver.
This morning at about 0620hrs, we received an information that some armed men invaded St. Philips Catholic Church in Ozubulu where the presiding priest was conduction an early morning mass.
Some residents and people of Anambra have since condemned the killing.
Osita Chidoka, a former Minister of Aviation, said he was saddened by the incident.
Gunmen stormed a Catholic church in a town in southeast Nigeria early Sunday, killing 12 worshippers, hospital sources and witnesses said.
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Police were at pains to stress this was not a Boko Haram attack in part because the terrorist group has become infamous for its assaults on churches, especially on Sundays and major feast days such as Easter and Christmas.
"We gathered that worshippers for 6 o'clock Sunday mass at St. Philip Ozobulu were in the service when a gunman dressed in black attire covering his face with a cap entered the church and moved straight to a particular direction and opened fire".
Security agents were said to have cordoned off the church.
"As a political leader, I totally condemn the Ozubulu Church shooting as dastardly, unjustifiable and callous".
National Secretary of the union, Shuaibu Usman Leman, who said the statement described the attack as "despicable cowardly act allegedly by a lone wolf, the attack is unequivocally detestable and must be addressed with all the seriousness it deserves and swiftly too".
He said the police had launched a manhunt on those behind the act and gave an assurance that everybody behind the act would be brought to justice.
He wondered why brothers could visit such attack on their people and urged those involved to "sheathe their swords".