The FBI has estimated that up to 1,100 people remain unaccounted for following the Maui wildfires that killed more than 100 people and devastated the historic town of Lahaina.

Steven Merrill, special agent in charge of the FBI’s Honolulu division, said at a press conference Tuesday that between 1,000 and 1,100 remain unaccounted for in the wake of the Maui fires. He said the FBI has narrowed down its list of unaccounted-for people, noting authorities have accounted for about 1,400 of the 2,500 who were originally reported as missing.

“We’re making tremendous progress, but no one on this stage will be happy, including myself, until we get that list as far as we can go,” Merrill said. “As the chief mentioned, we may not know in the end about everybody, but we are diligently working with immediate attention to get that list down to where we want it to get to, which is that we’re confident we know what happened to the best of our ability.”

Maui County officials said that as of Tuesday, at least 115 people had been confirmed to have been killed in the fires that swept the western part of the island. Officials said they had completed the search of one-story residential buildings in the area and were continuing to search multi-story residential homes and commercial properties.

Merrill encouraged residents to follow up on their missing person reports. Officials also urged family members to submit DNA samples to help identify the wildfire victims.

“If you have already submitted complaints to the Maui Police Department about a missing person, or to the FBI, or anyone else, please follow back up to ensure that they have the most up-to-date and accurate information, including dates of birth, what they look like, who they’re related to, further contact information,” Merrill said.