A motorist who drove into a tree was dead on the scene early Wednesday after someone shot him in the head in Jefferson Park on the Northwest Side. Around 2:55 a.m., the man, about 20 years old, was found in the driver seat of a silver SUV that struck a tree in the 5700 block of North Central Avenue with a gunshot wound to his head, Chicago police said. The unidentified man was pronounced dead at the scene, police said. Area 5 detectives are investigating but no arrests have been made.