An investigator for the Minneapolis Arson Unit has classified last week's fire at Walker Community United Methodist Church in south Minneapolis as an accident.
In a report issued Tuesday, investigator Sgt. Sean McKenna said the fire originated in an attic of the church and that it was mostly likely caused by a lightning strike.
The fire occurred May 27 during a strong thunderstorm.
Some observers cited in earlier reports said that two men left the scene before the fire. Tuesday's report stated that they were believed to be members of a group allowed to use the building, and that very few people had access to the area where the fire started.
The remains of the church, which was more than a century old, were demolished the morning after the fire. Some community members have accused city authorities of botching the investigation. City officials said the ruins of the building posed a safety hazard, and that investigators were able to examine the remains before demolition.
Five firefighters were injured in the blaze.