PEABODY – A Peabody man has been found guilty of four of the five counts he was charged with by a federal jury following threats to kill an undercover officer over Oxycodone pills.Earl Francis Hart, 49, was convicted of brandishing a firearm in a drug trafficking crime, being a felon in possession of a firearm, conspiracy to possess Oxycodone with intent to distribute and attempted possession with intent to distribute Oxycodone.Hart, who had previously been convicted of a felony, allegedly conspired to distribute Oxycodone on Sept. 18 and 19 of 2008, and then brandished a firearm in connection with that offense.Evidence at the trial revealed that on Sept. 19 at the Carriage House Motel on Route 1 north in Peabody, Hart held a loaded Iver Johnson semiautomatic .380 caliber to the head of an undercover Peabody officer, threatened to kill him and then robbed the sergeant of what Hart thought was 125 Oxycodone pills.U.S. District Court Judge Patti B. Saris set a sentencing for Jan. 27, 2011 at 2 p.m. Hart had previously been convicted of two prior serious violent felonies and the government had filed a notice of sentencing enhancement. Hart is now subject to a mandatory life term of imprisonment on the conviction for the brandishing count.The case is being prosecuted by Assistant U.S. Attorneys George W. Vien and Zachary R. Hafer of U.S. Attorney Carmen M. Ortiz?s Organized Crime Drug Enforcement Task Force.