Israel-Gaza-Lebanon updates: Nasrallah killed for tying Hezbollah cause to Gaza war

The U.S. Embassy in Jerusalem issued a security alert "temporarily" restricting travel for U.S. government employees and their family members to parts of northern and northeastern Israel.

"U.S. government employees and their family members have been temporarily restricted from any personal travel north of highway 65 toward Afula and north/northeast of highway 71 from Afula to the Jordanian border. Any official travel in this area will require approval. Approved travel will take place only in armored vehicles. This is provided for your information as you make your own security plans," the U.S. Embassy alert said.

Afula is a city in northern Israel.

"US citizens should take this into consideration when planning their own activities," the alert read.

-ABC News' Ellie Kaufman

At least 492 people were killed and over 1,600 injured in Lebanon early Monday as the Israeli military expanded its campaign against Hezbollah, according to the Lebanese Ministry of Public Health.

Among the deceased were 35 children and 58 women, the ministry said.

The Israel Defense Forces said they struck at least 800 targets in southern Lebanon on Monday morning.

In a statement, Israeli Prime Minister Benjamin Netanyahu claimed they were changing “the security balance, the balance of power in the North.”

"For those who have not yet understood, I want to clarify Israel's policy -- we do not wait for a threat, we anticipate it. Everywhere, in every arena, at any time," Netanyahu said. "We eliminate senior officials, eliminate terrorists, eliminate missiles -- and our hands are bent."

"Whoever tries to hurt us, we hurt him even more," he added.

Hezbollah senior commander Ali Karaki, who was targeted in Monday’s strike on Beirut, survived the attack, Hezbollah officials said.

Two senior Israeli sources confirmed to ABC News that Karaki had been the target of the strike.

At least six people were injured Monday in an Israeli strike on southern Beirut, according to Lebanese state media.

The Israel Defense Forces conducted the targeted missile strike on a residential building in Bir al-Abd, a southern suburb of Beirut.