Sunday's attack on St Francis Catholic Church in the Nigerian town of Owo killed 22 people and injured 50, an official from the National Emergency Management Agency said on Tuesday.
Unknown assailants attacked the congregation with guns and explosives during Pentecost Sunday mass. Authorities had not previously released any casualty figures. Media reports had said more than 50 people were killed.
It is not uncommon for conflicting casualty figures to emerge in the aftermath of disasters in Nigeria.
Authorities have not given any information about the identity of the attackers or their motive.
Police said on Monday they had recovered unexploded bombs as well as casings from bullets used in AK-47 assault rifles.
They said some of the attackers had positioned themselves among the worshippers while others fired into the church from different directions.
Survivors were being treated in hospital for lacerations, bullet wounds and blast injuries, doctors said.
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