Six people have died in an apartment fire in Hartland, Wisconsin.
The chief of police, Torin Misko, confirmed the number of fatalities, adding that formal identification of the bodies is yet to take place.
The fire reportedly broke out at 5am local time, at a four-family apartment complex at Mansfield Court, Hartland.
Firefighters arrived at the scene to a "large fire", before setting out to rescue residents from apartment units and balconies.
Crews from 15 fire departments and nine police departments responded to the incident.
Chief Misko said a criminal investigation into the incident is under way, with officials yet to determine what caused the fire.
The State Fire Marshal's office, the Waukesha Sheriff's Office, Wisconsin Crime Lab, and Hartland Police and Fire Departments are working on the investigation together.
So far, it has been alleged that the six fatalities were caused by gunshot wounds, administered by a shooter who went on to commit suicide, according to news reports.
Spencer Tracy from FOX6 News tweeted: " #BREAKING_NEWS @HartlandFire have confirmed 6 people have died from this morning’s apartment fire. @fox6now ", and TMJ4's Susan Kim tweeted: " #Breaking : Hartland Police Chief Torin Misko says six people found dead each suffered single gun shot wound. Misko says Connor McKisick's wound appears to be self-inflicted. Adds that accelerant was found in apartment unit. @tmj4."
The Red Cross confirmed that its disaster team attended the scene. A spokesman confirmed that 10 people survived the fire, from three separate units.
Out of the 10 survivors, five are said to be children, including a 15-year-old, two 13-year-olds, a 12-year-old, and an 8-year-old.
According to the Red Cross, Chief Misko said some escaped on their own and others were brought to safety by first responders.
He said: “Our initial response was for life safety. Once we determined that we provided that life safety assistance, then things slowed down into more of a recovery effort at that point.”
The superintendent of Hartland Lakeside School District released a statement to families regarding the fire, which read:
"Dear Families,
"This morning we were made aware of an apartment fire in the Hartridge subdivision. Some of our families have been affected but we have no further information at this time. We will be working with local agencies to support our students and families. Please keep these families in your thoughts.
"We ask that you do not call our school offices. We have no information to share at this time. As soon as we receive information from the Hartland Police Department we will update our families. We appreciate your patience and cooperation."
Hartland's village president Jeffrey Pfannerstill, also provided a response to the incident, saying the whole community is hurting after such a loss of life.
“It saddens me, it scares me, but I think it wakes us up to the fact that it doesn’t have to be a big city. It can be anywhere," he said.
