NMAC.

Narrative

FLT WAS PROCEEDING UNDER STL RADAR APCH CTL. WX WAS VMC. WE WERE ESTABLISHED ON RWY 30R LOC AT 5000 FT. WE THEN RECEIVED A CLRNC TO DSND TO 3500 FT. AS THE ACFT DSNDED THROUGH APPROX 4000 FT WE RECEIVED A TCASII RA TO 'CLB.' WHILE EXECUTING THE ESCAPE MANEUVER WE NOTICED A RED SYMBOL DIRECTLY UNDER THE ACFT SYMBOL ON THE IVSI WITH A SEPARATION NOTATION OF '00' FT. SHORTLY AFTER INITIATING OUR CLB CAPT OBSERVED AN LTT SLOWLY DIVERGING FROM THE L SIDE OF OUR ACFT AND DIRECTLY ABEAM; BUT NOW BELOW US. AT THE SAME TIME WE RECEIVED A 'CLR OF CONFLICT' ADVISORY. WE IMMEDIATELY ADVISED THE CTLR WE HAD RECEIVED AN RA AND HAD COMPLIED WITH TCASII COMMANDS TO CLB. THE CTLR THEN ADVISED US WE HAD LTT TFC OFF OUR L ON APCH TO RWY 30L AND THEN CLRED US FOR VISUAL APCH TO RWY 30R. THE REMAINDER OF THE APCH AND LNDG WAS UNEVENTFUL. AFTER LNDG; CAPT CONTACTED SUPVR AT STL TRACON AND WAS ADVISED THAT AT THE TIME OF THE INCIDENT IN QUESTION THE LTT HAD BEEN PROCEEDING ON A VISUAL APCH CLRNC TO RWY 30L. HE FURTHER STATED THIS ACFT HAD RPTED US IN SIGHT AND HAD BEEN INSTRUCTED TO MAINTAIN VISUAL SEPARATION.