Why some flames are blue and others are red?

Former U.S. Army soldier set off incendiary outside New York federal building: FBI

Suspect accused of setting fire outside NYC federal building

Wildfire smoke kills tens of thousands of people a year. Here's why and what you can do about it

FBI: Former soldier set off incendiary outside New York City federal building

Evacuation orders in place as Summit Fire burns more than 2,000 acres