10:47 AM PT -- The woman, Laneisha Shantrice Henderson, has been charged with attempted arson and interfering with government property. We've just obtained her mug shot.

A would-be arsonist tried to burn down the birth home of Martin Luther King Jr. in Atlanta -- but her plan was foiled by a bunch of tourists who filmed the ordeal and restrained her.

The 26-year-old woman was caught on camera Wednesday, holding a large plastic gasoline container and splashing the front of MLK's house with the flammable liquid.

Check out the video ... one of the tourists turns his camera on the woman and asks, "What are you doing?"

The woman turns to him and says, "What?" before waving him off and continuing to vandalize the historic home.

Two other people visiting the landmark grabbed the woman and held her down on the ground until Atlanta PD officers arrived and took her into custody.

The suspect, whose name was not released, was charged with criminal attempt arson and criminal attempt interference with government property.

She could also face federal charges since the house is operated by the National Park Service -- a federally run agency.

Atlanta Police Chief Darin Schierbaum gave credit to the good Samaritans, saying, “That action saved an important part of American history tonight.”

Atlanta Fire Department Battalion Chief Jerry DeBerry also pointed out the house could have been "engulfed in flames" within seconds if the witnesses hadn't come to the rescue.

The King Center -- established in 1968 to carry on MLK's legacy -- issued a statement on X, reading in part, "Tonight, an unfortunate incident occurred at the birth home of Dr. Martin Luther King, Jr. as an individual attempted to set fire to this historic property. Fortunately, the attempt was unsuccessful, thanks to the brave intervention of good Samaritans and the quick response of law enforcement."