NMAC.

Narrative

LOCATED 18 DME W OF TETERBORO VOR ON 275 DEG R AT 7000' MSL; FLT WAS CLRED BY N.Y. APCH TO DSND AND MAINTAIN 3000'. IMMEDIATELY PRIOR TO ACKNOWLEDGING DSCNT CLRNC AN ACFT WITH LIGHTS ON PASSED BELOW FLT WITHIN 200'. UPON ACKNOWLEDGING THE DSCNT CLRNC TO APCH CTL; WE ADDED THAT WE HAD EXPERIENCED A NEAR MISS WITH AN ACFT JUST SECS EARLIER. THE CTLR RESPONDED BY SAYING THAT I WAS THE ONLY ACFT ON THE SCOPE IN THAT SECTOR; AND ON THAT FREQ. HIS RESPONSE ALSO INCLUDED THE STATEMENT THAT IS WAS PROBABLY AN ILLEGAL ACFT IN THE TCA. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING: CAPT STATES F/O CONFIRMED NMAC WHICH HAPPENED SO FAST HE WONDERED IF IT COULD HAVE BEEN SOME OTHER PHENOMENON. BOTH PLTS SHOCKED AS NO TFC ADVISORY GIVEN. TRIED TO DETERMINE IF IT COULD HAVE BEEN ANY GND LIGHTING AS THEY WERE AT BASE OF OVERCAST. BOTH ARE SURE IT WAS AN ACFT; AND EVEN THOUGHT THEY MIGHT TAKE A WING HIT; THEIR BEST GUESS IS THAT WHAT THEY SAW WAS THE RIGHT WING LNDG LIGHT OF AN SMA. EVEN AT 250 KTS BELOW 10000'; CLOSURE RATE WAS RAPID. BOTH VERY SHOCKED.