What is the pink fire retardant being dropped on L.A. wildfires? Here's what to know.

Aircraft battling fires raging through the Los Angeles area are dousing the area with more than water: Hundreds of thousands of gallons of hot-pink fire suppressant have been dropped ahead of the flames in a desperate effort to stop them before they destroy more neighborhoods.

The deadly fires have displaced thousands of residents and destroyed more than 12,000 structures since they began last Tuesday, Jan. 7. Four major fires driven by strong Santa Ana winds have charred about 62 square miles, according to Cal Fire.

Fire agencies say the suppressants — most often used to fight forest fires — are an invaluable tool. But what is in them and are they safe?