Hi, everybody. It is 4 o'clock in New York. I'm Alicia Menendez in this afternoon for

Nicole Wallace, picking up coverage now of the ongoing conflict in Israel. It is just after

11 p.m. there, the waning moments of another brutal, deadly day on the ground. Things are

still extraordinarily fluid this hour, two full days after Hamas began its bloody attack.

At the moment, Israel says it's retaken control of its territory, although fighting continues.

The Israeli defense force has begun what it calls a full siege of Gaza, having amassed

a force of some 300,000 reservists, called up ahead of what could be a large-scale ground

invasion. It is an overwhelming tragedy, a horror story on a planetary scale. At least

1,200 people are dead. 570 people in Gaza and the West Bank. 700 people in Israel. Soldiers.

Children. The State Department says 9 Americans are among those killed and more may

be missing. One of the most urgent crises right now, the desperate search for hostages,

around 150 of them taken captive by Hamas and imprisoned, somewhere in Gaza. Their

fates unknown. And this afternoon, Hamas is threatening to execute them. Gaya Calderon was

on the phone with her mother as terrorists were inside their house. The phone died. And

now, she says she has no idea where her father, her sister, cousin with special needs, or

her 80-year-old grandmother with dementia are. As for her brother, recorded and circulated

online a 12-year-old boy, forcibly restrained, kidnapped, carried away to be used as a bargaining

chip. What heartbreak and what terror. Yoni Asher, meanwhile begging for the return of his

wife and his daughters, ages 3 and 5. Take a listen to what he told NBC News.

I tell them that be strong, hold on. I'm thinking about you. I'm working hard to try

in order to get you back. Stay strong. Try to be happy. Don't be afraid. You know, it's hard

for me to say those things when I don't really know in what terms, what conditions they're held.

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