OKLAHOMA CITY (AP) — Six teenage girls on a high school lunch break were killed when their small car with only four seats collided with a large truck hauling rocks, the Oklahoma Highway Patrol said Wednesday.

The crash occurred shortly after noon Tuesday in Tishomingo, a rural city of about 3,000 located about 100 miles (160 kilometers) southeast of Oklahoma City, the patrol said. Those killed included the 16-year-old driver, three 15-year-olds, and two 17-year-old passengers, according to the patrol.

While what led to the crash is unknown, it highlighted concerns of teenagers carrying other y...