Simon Williams, 56, a pastor, had been discharged from an intensive care unit on Friday before attending the “Higher Life World Conference”, where televangelist Chris Oyakhilome was said to perform miracles and cure the sick.
It was believed another person may have died in hospital after also attending the conference.
About six other seriously ill people were rushed from the stadium to hospital on Friday evening.
Hundreds of sick and disabled people queued outside the stadium on Sunday, the last day of the conference.
According to the report, the Advertising Standards Authority ruled last year that the Christ Embassy church could not prove its pastors could perform healing miracles, and had to withdraw all such television adverts.
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