TB Joshua and staff at his Synagogue Church of All Nations (SCOAN) have so far failed to disclose information to the investigation, the state government and emergency services said.
Some 67 South Africans died when a hostel for Joshua’s foreign followers collapsed last Friday, President Jacob Zuma said in Pretoria on Tuesday, with fears that the toll could rise further.
Rescue workers have been picking through the rubble with heavy lifting equipment and using sniffer dogs, although the National Emergency Management Authority (NEMA) said the search for survivors could end on Wednesday.
“The church is not co-operating with emergency workers at all,” NEMA’s spokesman for the southwest region, Ibrahim Farinloye, told AFP, giving the latest toll as 67 with 131 survivors.
“For the first three days of the incident, the church people were very hostile and prevented rescue officials access to the site.
“It was after the visit of the (Lagos state) governor (Babatunde Fashola) when he threatened to close down the church that we were allowed to work.
“Perhaps if we had had early access to the place we would have been able to save more lives.”
Thousands of people from across the world flock to SCOAN with promises of miracles and prophecies from Joshua, a high school dropout referred to either as “The Prophet” or “The Man of God”.
Joshua, who claims to have raised the dead and predicted the Malaysian Airlines MH17 plane crash and Boston marathon bombings has considerable clout in Nigeria and beyond.
Top-level politicians and even heads of state are among his flock, including Malawi’s former president Joyce Banda, who has called him her “spiritual father”.
But there was increasing anger on social media that he should not be above the law.
The preacher has not publicly commented on the deaths and instead tried to shift suspicion on to Boko Haram militants and a low-flying plane seen over the building before the collapse.
Since Friday he has only posted a series of Bible verses on his Facebook page and Twitter account. On Tuesday night, he tweeted: “Hard times may test me, they cannot destroy me.”
Zuma said five South African church tour groups totalling about 300 people were thought to have been at the Pentecostal church at the time of the tragedy.
But Pretoria’s ambassador to Abuja, Lulu Mnguni, told the eNCA news channel that lack of co-operation from the church authorities was making the situation difficult to assess.
“The numbers could still go up or down. We have put more people on the ground to assist us,” he said.
One South African travel agent, who asked not to be named, said some of the survivors flew back from Lagos on Sunday but were too distraught to recount their ordeal.
“It’s a sensitive issue. They don’t want to talk to anyone about what they saw. They are in shock, they are traumatised,” he said.
The investigation will look at Joshua’s claim of low-flying aircraft, Lagos state commissioner for town planning and urban development Toyin Ayinde told Nigeria’s Channels television.
Initial indications were that the building came down because extra floors were being added without strengthening the foundations and samples would be taken from the site, he added.
According to Joshua’s website scoan.org, three of the church’s previous buildings were destroyed before the new church – described as an “architectural masterpiece” – was built.
“There was only one architect involved in the planning – the Holy Spirit,” he said.