Hello from CNN, I'm Anna Sturla with the five things you need to know for Tuesday, January 2nd.

Hamas says one of its senior leaders was killed in an attack today in southern Beirut.

Israel's forces wouldn't comment on the attack to CNN,

but a former Israeli ambassador to the UN

congratulated Israeli security and intelligence agencies

on social media, attributing the killing to them.

CNN's Nara Bashir says this is a dramatic escalation.

There have been mounting concerns that we could see an escalation more broadly in Lebanon, not just centered around that border region

where we have over the last few days and weeks seen that exchange of fire we have

seen over the last few days that has been a group targeting Israeli targets across the border Israel

in turn carrying out airstrikes, drone strikes in Lebanese villages near the border region.

But this is a significant step up the targeting of a Hamas official, a significant Hamas official inside Beirut.

Israel's military is starting to draw down the number of soldiers on the ground in Gaza even as fighting continues.

The Palestinian Ministry of Health estimated today that almost 2 million people are now displaced in

Gaza.

CNN is unable to confirm that figure.

And in the Red Sea, Huthy rebels

are continuing to attack one of the world's most

important sea trade routes, saying they're

taking revenge against Israel for its military actions in Gaza.

Now shipping giant Mersk has suspended shipping

through the Red Sea and Suez Canal indefinitely.

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