A Bulgarian government jet has returned to Sofia with 89 nationals who were evacuated from Lebanon.

Prime Minister Dimitar Glavchev, who welcomed them at the Sofia Airport on Monday, said the government was discussing all options for future evacuations.

The Israeli military declared a military zone in parts of its northern border with Lebanon on Monday ahead of possible ground operations.

"The areas of Metula, Misgav Am, and Kfar Giladi in northern Israel have been declared a closed military zone. Entry to this area is prohibited," the military said in a statement.

Iran lost its most reliable ally in the Middle East when an Israeli airstrike killed Hezbollah leader Sayyed Hassan Nasrallah. But Iran isn't leading the charge to retaliate.

"By the grace and power of God, Lebanon will make the transgressing, malicious enemy regret its actions," Iran's Supreme Leader Ayatollah Ali Khamenei said in the wake of Nasrallah's death Friday. But the 85-year-old paramount ruler in Iran gave no mention of his country taking action over the death of a man he once praised as "an exceptional face in the world of Islam" after the Israel-Hezbollah war in 2006.

President Joe Biden said Sunday he would speak with Israeli Prime Minister Benjamin Netanyahu, and believes that an all-out war in the Middle East must be avoided.

"It has to be," Biden told reporters as he boarded Air Force One for Washington. "We really have to avoid it."

In just over a week, intensified Israeli strikes in Lebanon killed seven high-ranking commanders and officials from the powerful Hezbollah militant group, including the group's leader, Sayyed Hassan Nasrallah.

The move left Lebanon and much of the Mideast in shock as Israeli officials celebrated major military and intelligence breakthroughs.

Yemen’s Houthi rebels claim they shot down another American-made MQ-9 Reaper drone over the country, with videos purportedly showing a surface-to-air missile striking it. The U.S. military did not immediately acknowledge losing any aircraft.

The claimed attack comes as the one-year anniversary of the Israel-Hamas war in the Gaza Strip approaches. The Houthis have targeted ships traveling through the Red Sea over the war as U.S.-led airstrikes pound their positions in Yemen. That’s imperiled a waterway that typically sees $1 trillion of trade pass through it, as well as crucial shipments of aid to war-torn Sudan and Yemen.

Israel's assassination of Hezbollah leader Sayyed Hassan Nasrallah is a monumental and hugely demoralizing blow to the group he led for 32 years, marking a significant inflection point for Lebanon and the region.

Hezbollah's announcement of his death Friday triggered tears and celebrations across the Arab world, pointing to the widespread reach and influence of a divisive man who has been at the forefront of Middle Eastern politics for decades.

Lebanese officials have asked people who lost relatives in recent Israeli airstrikes to provide DNA samples to match with unidentified remains.

Lebanon’s Internal Security Forces on Monday called on residents across the country to visit police stations with an identity card to give their samples. It said more than one person from each family should provide a sample, if possible.

European Union foreign ministers called Monday for an immediate ceasefire between Israel and Hezbollah and have expressed support for U.N. peacekeepers in southern Lebanon.

“Arms should now be silenced, and the voice of diplomacy should speak and be heard by all,” EU foreign policy chief Josep Borrell told reporters after chairing an emergency meeting.

An Israeli strike on a Beirut apartment block killed four people on Monday, a Lebanese security source said, the first such raid on the heart of the city since the outbreak of the war in Gaza last year.

Israel has turned its focus from Gaza to Lebanon in recent days, carrying out strikes on Hezbollah targets that killed the Iran-backed group's leader Sayyed Hassan Nasrallah on Friday.