What was found
THE AIRCRAFT RETURNED TO DEPARTURE, DUE TO THE LEFT ENGINE ISSUE. DECLARED EMERGENCY AND PERFROMED UNEVENTFUL LANDING. LEFT ENGINE SEIZED, FAN WILL NOT ROTATE. FIRE DEPARMENT CONFIRMED FLAMES IN TAIL PIPE, BUT EXTINGUISHED UPON LANDING. ACCOMPLISHED A NR 1 ENGINE REPLACEMENT IAW 26L40071004 AND 26L00071015. SYSTEM TESTED NORMAL.