John Tracey , 24 , arrested for allegedly setting two fires Friday night . One of arsons investigated in Coatesville ; but not linked to others . He recently became a paid firefighter with the department .
Robert Tracey , 37 , arrested for allegedly setting two fires Friday night . String of arsons investigated in Coatesville ; Tracey not linked to others . Tracey recently became a paid firefighter with Coatesville department .