Two people are missing and 13 others were injured Saturday when two boats crashed head-on on the Colorado River. The accident, which occurred in California’s Moabi Regional Park, happened as people gathered in the popular water recreation spot to celebrate Labor Day weekend. Eric Sherwin, a spokesman for the San Bernardino County Fire District, said one of those wounded suffered life-threatening injuries, while six others were hospitalized with less serious injuries. Six others suffered minor injuries, he said. Authorities said several people were thrown off the boats by the force of the crash, two of whom were “presumed submerged.” Rescuers called off their search mission for the two late Saturday but resumed efforts on Sunday morning.