What was found
(CAN) DURING TAKEOFF, THE NR 2 ENGINE FIRE DETECTION WARNING WAS ACTIVATED. CREW RETARDED ENGINE POWER TO IDLE AND THE FIRE WARNING EXTINGUISHED. ACFT RETURNED TO THE POINT OF DEPARTURE. A SIMILAR EVENT OCCURRED ON THE SAME ENGINE, SAME ACFT BACK IN OCTOBER OF 2009, WHICH WAS IDENTIFIED AS AN AIRFRAME CABIN BLEED AIR LEAK IN THE NACELLE. TROUBLESHOOTING IS ON-GOING. MFG WILL INVESTIGATE TO ESTABLISH ROOT CAUSE AND SUPPLEMENT THE REPORT ONCE THE INFORMATION IS AVAILABLE.