One person was killed and six others were injured after two trucks were involved in a head-on collision just over the reservation line east of Flagstaff over the weekend. Summit Fire officials say the accident happened at around 6 p.m. on Saturday on Leupp Road about a mile-and-a-half into the Navajo Reservation. When medical crews arrived, they began triaging the scene. One person was pronounced dead at the scene. All six injured were transported to the hospital for treatment. Both vehicles were traveling at a high rate of speed at the time of impact. Navajo Nation Police are investigating the incident.