LAHAINA, Hawaii (AP) — The head of the Maui Emergency Management Agency resigned abruptly Thursday, a day after saying he had no regret about not using sirens to warn residents of wildfires that devastated the historic seaside community of Lahaina and killed at least 111 people.

That decision from the agency directed by Administrator Herman Andaya, coupled with water shortages that hampered firefighters and an escape route that became clogged with vehicles, has brought intense criticism from many residents. The lack of sirens has emerged as a potential misstep, and The Associated Press reported that it was part of a series of communication issues that added to the chaos.

Mayor Richard Bissen accepted Andaya’s resignation effective immediately, the County of Maui announced on Facebook. Andaya cited unspecified health reasons, with no further details provided.

“Given the gravity of the crisis we are facing, my team and I will be placing someone in this key position as quickly as possible,” Bissen said in the statement.

A day earlier, Andaya defended the decision not to sound sirens as the flames raged. Hawaii has what it touts as the largest system of outdoor alert sirens in the world.

“We were afraid that people would have gone mauka,” Andaya said, using a Hawaiian word that means inland or toward the mountain. “If that was the case, then they would have gone into the fire.”

The siren system was created after a 1946 tsunami that killed more than 150 on the Big Island, and its website says they may be used to alert for fires.

Andaya was to take part in a meeting of Maui’s fire and public safety commission on Thursday morning, but it was canceled. On Wednesday, he vigorously defended his qualifications for the job, which he had held since 2017. He said he was not appointed but had been vetted, took a civil service exam and was interviewed by seasoned emergency managers.

Andaya said he had previously been deputy director of the Maui County Department of Housing and Human Concerns and had been chief of staff for former Maui County Mayor Alan Arakawa for 11 years. During that time, he said, he often reported to “emergency operations centers” and participated in numerous trainings.

“So to say that I’m not qualified I think is incorrect,” he said.

Arakawa said he was disappointed by the resignation “because now we’re out one person who is really qualified.” Arakawa said Andaya was scrutinized for the job by the county’s personnel service.

“He was trying to be strong and trying to do the job,” Arakawa said about the wildfire response. “He was very, very heartbroken about all the things that happened.”

Hawaii Attorney General Anne Lopez said earlier Thursday in a statement that an outside organization will conduct “an impartial, independent” review of the government’s response and officials intend “to facilitate any necessary corrective action and to advance future emergency preparedness.” The investigation will likely take months, she added.