Police say Jalen Bradley, 18, tried to run away while in handcuffs, take gun from officer.... ....Bradley was arrested after he brought a gun to the Jan Mann Opportunity School in Miami Gardens, police said..... After Bradley was taken into custody, he tried to run away while in handcuffs and fought with an officer, attempting to take his gun, police said. Bradley later told police he would have shot the officer if he was able to take the gun away, police said. Bradley said he hates both security monitors and planned to shoot them as well, police said.