PHOENIX -- Authorities say a 13-year-old boy is dead and his father and younger brother critically injured after the pickup truck they were riding in struck a big rig on Phoenix's Interstate 17.
Arizona Department of Public Safety officials say the man and his two sons were driving Monday afternoon from Rock Springs to their Gilbert home when their vehicle drifted into the shoulder near Jomax Road.
The pickup struck the semi, which was pulled over along the highway because of a flat tire.
After the pickup hit the big rig, authorities say tow truck driving south on the I-17 hit the truck.
DPS says an 11-year-old boy in the pickup also was critically injured.
Officials say all southbound lanes of the I-17 were closed for hours after the 2:45 p.m. accident. It was reopened about 5:45 p.m.