A self-storage unit in Walla Walla was damaged Monday night.
According to the Walla Walla fire department, crews were called out to a possible structure fire in the 2900 block of Isaacs Avenue.
An alarm had alerted dispatchers to a possible fire at Mill Creek Self Storage at 7:17 p.m.
The fire fighters that first arrived on the scene reported that heavy smoke was coming from the middle section of storage units.
Investigators say an exterior light on the units overheated, melting wires and sparking the fire.
It's estimated that the fire caused about $25,000 worth of damage to the contents and property.
No one was hurt.

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