A 14-year-old boy pulled out a gun in a school cafeteria near Middleton on Monday and opened fire, hitting two fellow students, and then ran from the school, threw the weapon down and was apprehended nearby with the help of a police dog, the authorities said. Two other Madison Local Schools students also were injured, possibly from shrapnel or from running away. None of the injuries appeared to be life-threatening, Sheriff Richard Jones of Butler County said. The campus is about 30 miles north of Cincinnati. Sheriff Jones said there was a known motive, but he did not identify it. The boy was charged preliminarily with two counts of attempted murder, two counts of felonious assault, inducing panic and making terrorist threats.