PHILADELPHIA — Two of the guns used in the shooting outside Roxborough High School last month, which left a 14-year-old dead and four teens injured, later ended up in the hands of a Philadelphia sheriff’s deputy who then illegally resold the weapons to a federal informant, according to a court filing unsealed Thursday. Samir Ahmad, 29, a four-year veteran of the department, was arrested at work last week as part of an FBI gun-trafficking investigation, the records say. In April, an informant set up a controlled gun buy with Ahmad, where he paid Ahmad $1,150 for a Smith & Wesson .38 Special rev…
