Dozens of people have been killed by Israeli strikes in Lebanon, including 20 who died after a strike flattened a multi-story residential building in central Beirut overnight, according to Lebanese officials.

The escalation comes after a U.S. envoy traveled to the region to pursue a deal to end months of fighting between Israel and Hezbollah.

The Israel Defense Forces continued its intense airstrike and ground campaigns in Gaza -- particularly in the north of the strip -- and in Lebanon, with Israeli attacks on targets nationwide including in the capital Beirut.