MIAMI (AFP) - Police in Tampa, Florida, have arrested a 17-year-old youth accused on plotting a bombing attack at his former high school, aiming to top the death toll of the 1999 Columbine massacre, officials said Wednesday. The youth "mentioned his desire to cause more casualties than were suffered at Columbine," Tampa Police chief Jane Castor said in announcing the arrest Tuesday of Jared Kano. "We had officers find material in his room that could be used for making explosive devices... the material that they found included fuel sources, shrapnel, plastic tubing, timing and fusing devices within his room."