At least 100 people were killed by the collapse of a church in southeastern Nigeria, a resident and photojournalist who visited the town morgue said today but officials put the death toll at just 27.

"At Uyo teaching hospital where I am now I could see over a hundred corpses, many are heaped on top off each other on the floor," said photojournalist Ini Samuel.

State police spokeswoman Cordelia Nwawe said 27 had been killed and 30 injured when the Reigners Bible church in AkwaIbom state capital Uyo collapsed during a service yesterday.

State emergency agency NEMA said in a statement that six people had been killed and 115 injured.

President Muhammadu Buhari expressed his condolences, telling "the governor and the people of Akwa Ibom State, the deep sorrow of his family, the government and the entire people of Nigeria over the many deaths and injury recorded following the incident," a presidential spokesman said in a statement.

The governor of Akwa Ibom state, who was at the church but was not injured, said on his Facebook page that "we have never had such a shocking incident in the history of our dear state".

In September 2015, 115 people including 84 South Africans, were killed in Lagos in the collapse of a church belonging to the famous televangelist TB Joshua.

Buildings collapses are frequent in the West African nation and often blamed by officials on lack of construction permits and the use of cheap materials amid widespread corruption.

Critics say Nigerian authorities tend to understate the death toll at such accidents or suicide bombings by the Boko Haram jihadist group in the north of the country.

During at gas plant blast in southern Nigeria a year ago the presidency said "tens of people" had been killed while witnesses counted more than 100 bodies. Police had then just confirmed eight dead.