The Marco Polo high-rise fire that killed three people July 14 and caused at least $100 million in damage was not intentionally set, but investigators continue to search for the cause, the Honolulu Fire Department said Tuesday.

Investigators from the Honolulu Fire Department, Honolulu Police Department and federal Bureau of Alcohol, Tobacco, Firearms and Explosives along with private investigators representing insurance companies still have not determined what caused the fire to break out in a 26th-floor unit, HFD Capt. David Jenkins said.

But they know it was not triggered by cooking. And, Jenkins said, “At this time there has been no indication that this fire was intentionally set.”

Out of 568 residential units in the 36-story building, more than 80 units were damaged, including 30 that were destroyed, mostly on the 26th through 28th floors.

The Fire Department normally does not send updates of fire investigations that have no known cause, but Jenkins said the department is trying to address rumors that began flying even as firefighters were still battling the seven- alarm fire at 2333 Kapiolani Blvd.

“Rumors run rampant,” Jenkins told the Honolulu Star-Advertiser. “Especially with the lack of any official statement or official information, people fill in the gaps with rumors on social media or word of mouth. There are a large amount of units that have to be inspected and recorded and tabulated. For the size and scope of this fire, we want to be able to give the community a sense that the investigation is ongoing and there are some things that have been ruled out.”

Tom Schmidt lives on the 26th floor in Unit 2603, near where the fire started in Unit 2602. He said he has been hearing all kinds of rumors of illegal activity and doesn’t believe any of them.

“I don’t think it was intentional, but it started for sure in my neighbor’s unit,” Schmidt said.

Schmidt and his wife, Brigida, will have to rebuild their apartment from the hallway to the lanai.

“We’re going to have to pull everything out: ceilings, drywall, floors, cabinets,” he said. “The heat was so intense.”

Firefighters responded to the first alarm at 2:17 p.m. and battled the fire for more than four hours as it spread from the 26th floor. It was under control by 6:32 p.m. and extinguished by midnight.

In addition to the three fatalities, 12 people received medical treatment, and five were transported in serious condition to hospitals. One firefighter was transported and treated for heat exhaustion.

Insurance companies could end up paying more — or less — than the $100 million damage estimate, Jenkins said.

Whatever the costs of the fire, “unfortunately it’s excruciatingly high no matter how you look at it,” Jenkins said. “It’s undoubtedly one of the most destructive fires in Honolulu in recent history.”