One person is dead and four others have been sent to the hospital following a mysterious odor in Denver. 

The Denver Fire Department initially responded to an odor investigation at a multi-family structure near the intersection of Ensenada Street and East 41st Place — in the Green Valley Ranch neighborhood next to Ensenada Park — around 8 a.m. on Tuesday, according to a social media post from the fire department.

Residents of the home called 911 and reported that they were having trouble breathing.

Fire crews and Denver Health paramedics responded to the scene and the assisted several people in the area, according to the initial reports.   

One person was pronounced deceased, and four — two adults and two children — were taken to a nearby hospital around 10 a.m., according to a subsequent social media post. First responders also assisted two people, bringing the total number of victims to seven. 

The Denver Police Department also responded to the scene to assist the fire department in investigating the cause of death. There is no danger to anyone outside of the building where the order was reported, a spokesman for Denver Fire said.

“We can say at this time there’s no indication that it is suspicious or criminal in nature,” a spokesperson with the Denver Police Department told The Denver Gazette.

This story is developing.