>>> BREAKING NEWS, NEVER BEFORE 
SCENE VIDEO OF THE BOSTON 
MARATHON ATTACK AT THE MOMENT 
THE BOMB GOES OFF.
IN ONE VIDEO SHOWN FOR THE FIRST
TIME IN COURT TODAY DURING 
DZHOKHAR TSARNAEV'S TRIAL, HE 
APPEARS TO BE SEEN.
HE'S CIRCLED THERE.
YOU CAN SEE HIM ON YOUR SCREEN.
HE'S WATCHING THE MARATHON.
THE FIRST BLAST GOES OFF.
THE CROWD TURNS TO LOOK AND 
DZHOKHAR TSARNAEV WALK AWAY AND 
THE SECOND BLAST DETONATES. 
>> NEARLY FOUR HOURS AFTER THE 
RACE BEGAN, THE BROTHERS WERE AT
THE RACE.
THE TWO SPLIT UP.
TAMERLAN AT THE FINISH LINE.
MULTIPLE IMAGES SHOW DZHOKHAR 
TSARNAEV STANDING BY HIMSELF FOR
SEVERAL MINUTES, AMONG SEVERAL 
CHILDREN SPECTATORS.
DZHOKHAR TSARNAEV MOVES QUICKLY 
IN THE OPPOSITE DIRECTION, 
REACHING THE CORNER JUST AS THE 
SECOND BOMB DETONATES, NEITHER 
DZHOKAHAR OR TAMERLAN.
HE LEAVES TO SWAP THE MILK 
BEFORE GETTING BACK INTO THE 
PASSENGER SIDE OF A CAR.
THE DRIVER SPEEDS OFF.
THAT NIGHT, ON ONE OF TWO 
TWITTER ACCOUNTS UNDER HIS NAME,
DMOOS DHAS DZHOKAHAR AIN'T NO 
LOVE IN THE HEART OF THE CITY.
HE'S SEEN HERE AT THE UNIVERSITY
FITNESS CENTER WITH A FRIEND AND
STAYING FOR AN HOUR.
THE FBI GATHERED 4,000 HOURS OF 
SURVEILLANCE PHOTOS VIDEOS, FROM
THAT DAY.
PHOTOS OF THIS WOMAN, THE SCARS 
ON HER STUMPS VISIBLE, WAS 
WHEELED UP A RAMP TO TESTIFY.
SHE SAID IT DID EXACTLY WHAT IT 
WAS DESIGNED TO DO, TEAR THE 
SKIN AND MUSCLES AWAY LEAVING 
BODY PARTS EXPOSED.
SHE SAW HER HUSBAND'S
