A huge truck fire spread into nearby brush and trees on Interstate 5 Tuesday morning, blocking traffic and sending a billowing plume of smoke over the area. Fire crews and police responded to the scene, in the northbound lanes of I-5 just south of Martin Luther King Jr. Way, at about 10:20 after receiving reports of a fire. They found a 20-foot flatbed truck fully ablaze upon arrival at the scene. Firefighters quickly extinguished the blaze before it could spread any farther. Video from the state Department of Transportation traffic cam showed huge flames and plumes of smoke spewing skyward from the blaze.