GEOFF: LISA, AS ALWAYS, GREAT TO

SEE YOU.

TURNING NOW TO THE DAY'S OTHER

HEADLINES, TURKISH OFFICIALS SAY

SIX PEOPLE ARE DEAD, AND AT

LEAST 80 MORE ARE INJURED,

FOLLOWING A LARGE EXPLOSION IN

THE HEART OF ISTANBUL.

SECURITY FOOTAGE CAPTURED THE

BLAST AND ITS IMMEDIATE

AFTERMATH.

OFFICIALS FEAR THE DEATH TOLL

COULD RISE.

THE CAUSE OF THE EXPLOSION IS

UNCLEAR, BUT TURKEY'S PRESIDENT

HAS CALLED THE DEADLY INCIDENT

AN ATTACK.

AND BACK HERE AT HOME, OFFICIALS

IN DALLAS CONFIRM THAT A MID-AIR

COLLISION AT AN AIR SHOW

YESTERDAY KILLED SIX PEOPLE.

BOTH OF THE PLANES WERE WORLD

WAR II-ERA, ONE, A MASSIVE

FOUR-ENGINE BOMBER.

THE FAA AND THE NTSB HAVE

LAUNCHED INVESTIGATIONS.

STILL TO COME ON "PBS NEWS

WEEKEND," WE CHECK IN ON THE

UNITED NATION'S ANNUAL CLIMATE

SUMMIT.

AND OUR WEEKEND SPOTLIGHT WITH

MEDIA MOGUL, BYRON ALLEN.

>> THIS IS "PBS NEWS WEEKEND,"

FROM WETA STUDIOS IN WASHINGTON,

HOME OF THE "PBS NEWSHOUR,"

WEEKNIGHTS ON PBS.