An apartment fire has left one dead and multiple residents displaced.

The City of Denton Fire Department reported on social media that it had responded to reports of a fire at Ridgecrest Apartments in the early morning hours of December 3. The individual reporting the fire told the department that multiple people were trapped on the structure’s upper levels.

“A DFD fire engine and ambulance arrived on scene within 6 minutes and reported heavy fire conditions and multiple victims trapped. Crews immediately went to work on fire attack and victim removal, with one successful victim rescue from a second-story unit,” stated the Denton Fire Department in its post. “During the search for potential victims, fire crews did locate one deceased male.”

The fire was upgraded to a two-alarm fire in under an hour, with four medical intensive care units, three chief officers, four fire marshals, one truck, and seven fire engines responding to the scene. Firefighters managed to get a handle on the flames at 2:47 a.m.

The identity of the deceased man has not been released by authorities yet. The Denton County Medical Examiner’s Office is expected to identify the victim after notifying his next of kin.

Officials have not yet determined the cause of the structure fire.

“At this time, the DFD Fire Marshal’s Office has ruled this fire as Undetermined due to the number of possible heat sources and a large volume of contents in the apartment,” the fire department said. “Eight units in the building were heavily damaged.”

Officials reported that the fire ultimately left over 20 people displaced from their homes. Red Cross and the apartment complex’s management have since found alternate housing for the affected residents.