A vegetation fire burned approximately 5 acres in the Santa Ynez Valley on Wednesday afternoon before forward progress was stopped, according to emergency radio reports.
At approximately 2:30 p.m., personnel from the Santa Barbara County Fire Department and Los Padres National Forest began responding to a report of a fire on the 5600 block of Armour Ranch Road.
A witness claimed an explosion occurred near a transformer in the area.
The blaze was burning in light fuels with a moderate rate of spread, according to firefighters.
Crews also were alerted to be cautious due to power lines in the area.
Firefighters estimated the blaze had the potential to burn up to 50 acres.
In addition to ground crews, a helicopter also responded to the incident, but incident commanders said they did not need fixed-wing aircraft.
An investigator was called to the scene to search for the cause.