Authorities say two people were in a mobile home in eastern Sioux Falls when it caught fire.
The fire broke out around 6:45 p.m. Monday at a home off of Rice Street.
Everyone inside was able to escape unharmed, but two dogs in the home have not been found.
By the time firefighters arrived, half of the home was engulfed in flames and smoke could be seen from Interstate 229.
Firefighters were able to contain it and prevent the fire from spreading to nearby homes.
“I guess right now our investigator is here on scene and we really don't know a cause. And at this point, we don't really have a point of origin where the fire even started,” Sioux Falls Fire Rescue Battalion Chief Jay Titus said.
The Red Cross is helping the family.