The head of Maui County’s emergency management agency resigned on Thursday, a day after he defended his decision to not activate sirens during catastrophic wildfires that have taken more than 100 lives.

Maui Emergency Management Agency administrator Herman Andaya cited health reasons for his resignation, which took immediate effect.

Andaya was asked Wednesday whether he regretted not activating emergency sirens as wildfires spread across West Maui: “I do not,” he said at a press conference.

Andaya explained that the sirens are primarily used for tsunamis and the public is trained to seek higher ground. However, he argued that escaping to higher ground would have been dangerous during the wildfires.

“We were afraid people would have gone ‘mauka’,” Andaya said, using a Hawaiian word for mountainside. “And if that was the case, they would have gone into the fire.”

Maui County Mayor Richard Bissen announced that a replacement for Andaya will be appointed soon in light of the ongoing crisis.

“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 stated in a press release on Thursday.

The devastating wildfires have claimed the lives of at least 111 people as of Wednesday, making it the deadliest wildfire in the U.S. in over a century and the worst disaster in Hawaii state history.

State and local emergency management officials are under increasing scrutiny over their response and whether enough was done to alert the public as the wildfires spread.

Hawaii Attorney General Anne Lopez announced on Thursday that an independent investigator will be appointed to review the state and local response to the wildfires. The aim is to provide an impartial and independent assessment.

Hawaii Governor Josh Green clarified that the review is not a criminal investigation but an effort to ensure safety during future disasters.