She was held back from her release in 2018 because she refused to recount her faith in Christ.
The Uromi diocese is expected to release additional details about the priest’s release.
Local news outlets have also reported that several children were kidnapped at the same time.
"The government is certainly not doing enough to protect both Christians and Muslims."
The organisation, representing 600 million evangelicals in over 130 countries, also called for perpetrators to be held to account.
It is estimated that at least five million Christians participated in marches in 28 of the country's 36 states.
There have been two large attacks that took place on January 26 and 27.
Information about the woman killed with Nnadi is not yet available.
Statistics show that the persecution of Christians in Nigeria is extreme.