The fire, reported on the Mexico side of the international border, sent ash and smoke into the air in some sections of San Diego County.
Schools in the South Bay will be open Thursday despite heavy smoke and ash in the air from a fire across the U.S.-Mexico Border.
Mexico asked Cal Fire for help in fighting a 600-acre fire that created such smoke and ash it was visible across southern San Diego County Wednesday.
The fire was burning south of Tecate Peak on the Mexico side of the international border and created a large plume of heavy smoke that captured the attention of San Diego residents on alert because of the current red flag warning.
People in Imperial Beach, Nestor and San Ysidro reported seeing ash in the air and on the ground according to their posts to NBCSanDiego's Facebook page.
Sweetwater Union High School District officials said school would be in session tomorrow as the air quality has cleared. School staff will be checking air filters and replacing any as needed.
Firefighters estimated the smoke cloud at about 1/2 mile high and blowing off shore.
No reports of damage or homes threatened.
Chula Vista Fire Department sent three to four engines to the area of J and 4th Streets according to an NBC 7 San Diego news crew. Once there, the engines turned off their lights and returned to the station.
San Diego County was under a red flag warning with conditions ripe for fire. Earlier Wednesday, fire was reported in Rincon near Harrah's Casino and a fire burned 12 acres in Del Sur north of Rancho Penasquitos.
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