Mortuaries in the city of Uyo are overflowing from Saturday's tragedy, medical director Etete Peters of the University of Uyo Teaching Hospital told The Associated Press.

The Reigners Bible Church International was still under construction and workers had been rushing to finish it in time for Saturday's ceremony to ordain founder Akan Weeks as a bishop, congregants said.

Hundreds of people, including Akwa Ibom state Governor Udom Emmanuel, were inside when metal girders crashed onto worshippers and the corrugated iron roof caved in, they said. Emmanuel and Weeks, who preaches that God will make his followers rich, escaped unhurt.

Screaming survivors were streaming out and there were cries from injured victims when computer program analyst Ukeme Eyibio rushed to the scene.

"There were trapped bodies, parts of bodies, blood all over the place and people's handbags and shoes scattered," Eyibio said in a telephone interview.

He had parked his car outside the complex to make a phone call, heard a deafening explosion he thought was a bomb only to see that the church had disappeared, he said

Eyibio and three others managed to drag 10 wounded people from an overflow area for of worshippers just outside the collapsed church but they did not enter the main structure because a construction worker among them warned of the danger of a further collapse. The worker called his boss at Julius Berger construction company, who sent a crane to help lift debris off bodies.

While they waited for the crane, Eyibio tried to help a man whose legs were trapped under a steel girder. "I rushed to my car, got out the tire jack and used that to get the beam off his legs," he said.

"We managed to get him out but we saw others dying all around us," Eyibio, 27, said. "I'm so traumatized I could not sleep last night for the horrors repeating themselves in my mind."

Many uncounted victims are in private mortuaries scattered across Uyo, youth leader Edikan Peters said. He said some people are secretly taking the bodies of relatives to their homes because mortuaries are overcrowded and some do not have refrigeration.

A crane is being used to lift debris believed to be hiding the bodies of more victims, said Peters.

Peter said he tallied 90 bodies before he was told to stop counting on Saturday night.

Journalists at the scene charge that church officials are trying to prevent them from documenting the tragedy, trying to seize cameras and forcing some to leave the area.

The governor's spokesman, Ekerete Udoh, said the state government will hold an inquiry to investigate if anyone compromised building standards. Buildings collapse often in Nigeria because of endemic corruption with contractors using sub-standard materials and bribing inspectors to ignore shoddy work or a lack of building permits.

In 2014, 116 people died when a multi-story guesthouse of the Synagogue Church of All Nations collapsed in Lagos, Nigeria's largest city. Most victims were visiting South African followers of the megachurch's influential founder TB Joshua.

Two structural engineers, Joshua and church trustees have been accused of criminal negligence and involuntary manslaughter after a coroner found the building collapsed from structural failures caused by design and detailing errors.

But Lagos state government efforts to bring them to court have been foiled by repeated legal challenges that have delayed a trial.