The employees of the non-profit had evacuated the brand-new building before the explosion occurred
Farmington explosion
Credit: Donna Perry/Sun Journal via AP

One firefighter died and six more were injured when a propane explosion destroyed the office of a non-profit organization in Maine on Monday morning.

The central office of LEAP Inc. was evacuated just after 8 a.m. after employees smelled gas in the brand-new building, which had only begun construction last fall, Farmington Town Selectman Scott Landry tells PEOPLE.

Firefighters and the building’s maintenance manager were entering the building when the explosion occurred.

One firefighter was killed, while six were transported to the hospital. One of those six was later taken to Boston by air ambulance, according to Landry.

LEAP Inc. is a non-profit dedicated to helping adults with developmental, cognitive and intellectual disabilities, according to its website. No clients were in the building at the time of the explosion, said Landry.

He noted there is nothing but a “hole” left where the building once stood.

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Video captured by onlookers and shared to social media shows debris cluttering the air amid plumes of smoke.

Kim Hilton, who works at the nearby University of Maine at Farmington, told the Associated Press that the blast rocked her building, too.

“It felt like someone hit our building with a vehicle,” she said.

The university confirmed in a statement that none of its students were involved with LEAP, but noted that the full effect the explosion would have on the community remains to be seen.

“As we know and cherish, the Farmington and UMF communities are closely knit. In the coming days, we will learn how the incident has directly affected colleagues, neighbors, and friends we care deeply about,” the statement read. “Our thoughts and prayers are with the people who have been affected by the explosion.”

Gov. Janet Mills also addressed the incident on Twitter, writing she was “closely monitoring” the situation with help from the Department of Public Safety.

“Per protocol, the State Fire Marshal’s Office will thoroughly investigate the cause and origin of this devastating explosion,” she wrote. “Our hearts go out to all those impacted by this tragedy, especially to the loved ones of the firefighter lost and others injured. I am grateful for the work of first responders who are at the scene and urge Maine people to avoid the area.”

Spokespersons for the Farmington Fire Rescue Department and LEAP Inc. did not immediately respond to PEOPLE’s request for comment.