Fire crews have extinguished a yacht fire that sparked overnight in Northwest Miami-Dade. Heavy smoke filled the air near the 3600 block of Northwest South River Drive, early Sunday morning. Miami-Dade Fire Rescue crews were at the scene putting out the flames. The boat fire has since been extinguished. However, the yacht was left a total loss. Units remained at the scene to contain fuel from the vessel and minimize environmental impacts. No injuries were reported. The cause of the fire remains under investigation.