TAMPA, Fla. (AP) — At 17 years old, Jared Cano had been expelled and had several run-ins with the law, though none of the charges from burglary to drug possession had been pressed. When Tampa police, who periodically checked on the teen because of his troubled past, were tipped off that Cano was plotting to bomb the school that had kicked him out a year earlier, they thought the information was plausible enough that they knocked on his apartment door and his mother let them search the place. Cano had amassed shrapnel, plastic tubing, timing and fuse devices to make pipe bombs, all for a plot in which he intended to cause more casualties than the Columbine High School massacre where 13 were killed before the two student attackers killed themselves, police said Wednesday.