ALEXANDRIA — Investigators worked to learn what caused a massive fire that wiped out part of downtown Alexandria in western Minnesota.

More than 100 firefighters battled a blaze Tuesday that destroyed RM Tattoo, Raapers Eatery & Ale, Charlie’s Bazaar and Little Darlings Children’s Boutique.

About two dozen tenants who lived in apartments above the stores were evacuated safely.

Firefighters used a drone with thermal imaging for the first time, according to city spokeswoman Sarah Stadtherr. The Star Tribune  says it allowed them to locate hot spots and more effectively use their hoses.

Carlette Vernlund, who owns Charlie’s Bazaar, said she’ll be meeting with her insurance agent this week to determine how to proceed.

Pam Botker is co-owner of Creative Touch and president of the city’s Downtown Merchants Association. She said her business and others not directly affected by the fire have significant smoke damage.

“We have to gut our store and rebuild,” Botker said. “We’ll all help each other out. We’ve been talking and whatever we have to do to rebuild, we’ll do that.”