The Roosevelt Island Operating Corp ( RIOC ) issued this advisory at 6:58 AM

THE ROOSEVELT ISLAND BRIDGE GOING ON AND OFF THE ISLAND IS TEMPORALLY SHUT DOWN BY NYPD. DUE TO A VEHICLE ACCIDENT ON 36 AVENUE AND VERNON BLVD.

followed by another at 8:05 AM:

THE 36TH AVENUE ROOSEVELT ISLAND BRIDGE IS REOPENED FOR ALL VEHICLE TRAFFIC. HOWEVER, DUE TO A VEHICLE ACCIDENT AND CRIME SCENE INVESTIGATION, TRAFFIC DELAYS ARE EXPECTED, WHILE TRAVELING TO AND FROM ROOSEVELT ISLAND VIA THE BRIDGE.

Image From Google Maps I asked Roosevelt Island Public Safety Department Acting Chief Kevin Brown for more info on the traffic incident. Chief Brown replied:

… according to NYPD, at about 5:30 am there was a two car collision on 36th avenue and Vernon Blvd. A F/W/38 was transported from location to Cornell hospital via EMS in serious condition and likely to die due to head injuries. NYPD is still investigating.

The NY Daily News adds: