HONOLULU (AP) — The Maui Fire Department is expected Wednesday to explain exactly how the deadliest U.S. wildfire in more than a century was sparked last year.

The historic Maui town of Lahaina was destroyed and 102 people were killed the disastrous wildfire. Several agencies have investigated the fire, detailing the poor conditions — including hurricane-force winds and emergency response missteps — that contributed to the tragic outcome. But so far, those reports have stopped just short of analyzing the fire’s origin and cause, leaving that to the Maui Fire Department and the U.

S. Bureau of Alcohol, Tobacco, Firearms and Explosives. The Maui Fire Department asked the ATF to help with the cause and origin investigation last year, and the ATF’s findings will be included as an appendix to the department’s report.

What is already clear: Many things went wrong before and during the disaster. The National Weather Service gave advance warning that a hurricane passing far offshore would bring strong winds to the island, dramatically raising the fire danger. But an investigation by the Fire Safety Research Institute for the Hawaii Attorney General’s office found that officials prepared for the fire danger despite the warning.

A Hawaiian Electric early on the morning of Aug. 8, sparking a fire in overgrown brush near the edge of town. Fire crews responded and stayed for several hours until they believed the fire was extinguished.

After they left, flames were spotted agai.