Firefighters backed up by aerial tankers and helicopters held a wildfire to 69 acres Monday after it broke out on Caballo Lane about 3¼ miles northeast of Los Olivos, according to the Santa Barbara County Fire Department.

Several scattered homes were threatened by the flames, leading to the evacuation of residents, and the Red Cross set up an evacuation center at Los Olivos Elementary School, fire officials said.

One barn was damaged by flames on Avenida Caballo, but all other structures were left unscathed. Residents were allowed to return home about 6 p.m. Monday, and full containment was expected by Wednesday, County Fire officials said.

But the Caballo fire and the Peak fire that broke out Sept. 4 in the Los Padres National Forest served as a reminder that the Central Coast is heading into its peak wildfire season, so residents and visitors need to be extremely vigilant about clearing their homes and cautious with sources of ignition, fire officials said.

The fire that erupted around 2:15 p.m. near Avenida Caballo and Caballo Lane poured heavy smoke into the air as County Fire called a second alarm on the fast-moving flames.

In all, 16 engines, five hand crews, four bulldozers and three water tenders — a contingent of about 200 people — descended on the fire, said County Fire spokesman Capt. Daniel Bertucelli.

Four fixed-wing tankers and three water-dropping helicopters attacked the fire from the air as ground crews worked to build a line around the flames amid 93-degree heat and 15 mph winds, said County Fire spokesman Capt. Mike Eliason.

Firefighters stopped the forward progress of the fire about 5 p.m., and the fixed-wing tankers were released, although helicopters continued to make water drops around homes, Eliason said.

Helicopters were released shortly after that, Eliason said.

Bertucelli said seven engines and two hand crews remained at the scene overnight, and as of noon Tuesday the fire was 70% contained, with full containment expected by 6 p.m. Wednesday.

The size of the fire was initially set at just over 50 acres, then revised down to 40 acres. But after GPS mapping, it was revised upwards again to 69.51 acres Tuesday afternoon.

Four engines, two hand crews and one water tender were still at the fire Tuesday, and Bertucelli said fire crews there would be on patrol status Wednesday to make sure the fire doesn’t rekindle.

The Caballo fire broke out just two days after a wildfire burned about 8 acres in Los Padres National Forest east of Zaca Lake

County Fire crews initially responded but were released as U.S. Forest Service firefighters were able to contain the flames in rugged hilltop terrain and remained at the scene overnight.

The causes of both fires are under investigation.