MANKATO — A fire that killed two children and critically injured their mother last August was caused by an accidental candle fire, according to the state fire marshal’s investigation report.
The fire occurred at about 2 a.m. Aug. 25 at 233½ Bradley St. Mankato Fire was dispatched to the structure fire with flames showing from the upper level, according to the report. Fire crews found heavy fire damage on the second floor of the duplex-style home.
Four occupants escaped the upstairs apartment, while a 6-year-old boy was found deceased inside. A 1-year-old later died at the hospital.
Based on fire patterns, fire dynamics and witness information, the report determined the fire originated along the north wall of an enclosed porch attached to the second-floor apartment. The ignition source was identified as a lit candle, with lint buildup in a wall cavity serving as the first fuel ignited.
Investigators ruled out natural gas, electricity and lightning as possible causes. Natural gas service to the upstairs unit had been shut off in June 2025, and electrical service had been disconnected more than a week before the fire, according to the report. A camp stove used by the family for cooking was found in another room and was not involved in the fire’s origin.
The victims were later identified as Aiden, 6, and Annika, 1, and the toxicology reports show carbon monoxide poisoning due to inhalation of products from a fire to be the cause of death.
Their mother, Deanna Lynn Lenzen, suffered severe smoke inhalation and spent weeks in a medically induced coma. According to updates posted to a GoFundMe page organized by friends, Lenzen has since been released from the hospital and continues her recovery.
“Devastated is an understatement. Time stops moving. It’s really difficult to do anything. It’s hard. There’s not a moment that’s easy,” Adam Tillson, Lenzen’s partner, said in an August Free Press article.
Multiple candles were documented on window sills inside the enclosed porch, which investigators said were being used for lighting in the evening. The report noted it could not be determined how the candle came into contact with combustible material, though possible scenarios included the candle being knocked over by a pet or inadvertently tipped by an occupant.
The investigation found no evidence of an intentionally set fire, and the case has been closed pending any new information, according to the fire marshal’s report.