More than two-dozen calves were killed in a barn fire in central Minnesota early Thursday morning.
The Stearns County Sheriff's Office said it was called to the Wuertz Dairy Farm in Spring Hill Township after a barn caught fire just before 1 a.m.
The cattle barn was "fully engulfed" in flames by the time they arrived, with the homeowners, Peter and Lisa Wuertz, of Melrose, unaware of the blaze until they were woken up by a passerby.
The owner was able to get one of the gates open to release the 30 cows trapped inside.
Unfortunately 25 calves were killed during the fire, with the barn a total loss.
The cause of the fire is now under investigation.
More on barn fires
The National Fire Prevention Association (NFPA) says that the leading cause of fires in barns and stables is "defective or improperly used heating equipment."
This is mainly an issue during winter months, when owners use space heaters, water heaters and heated buckets to keep their animals warm.
Most barn fires, the NFPA notes, occur overnight, when there are fewer watchful eyes on the property.
HorseInfo.com notes that other causes of barn fires can include lit or smoldering cigarettes, faulty mechanical equipment such as tractors, faulty wiring, coffee pots, lightning and "spontaneous combustion of hay."