One week into the resumed Israeli military campaign in Gaza, U.S. officials and foreign policy experts are increasingly afraid Israels operation will fuel a broader conflict, drawing in Lebanon and expanding throughout the Middle East, potentially forcing American troops into the fight.

Biden administration officials at multiple government agencies have in recent days expressed concerns that Israel may be seeking American military aid for fighting in Lebanon, two U.S. officials told HuffPost. Such a step would mark a major escalation, almost certainly proving extremely deadly for civilians in both Lebanon and Israel. It could also force a confrontation with Iran, a regional heavyweight that backs the powerful Lebanese militia Hezbollah.

Officials were briefed on the Lebanon concerns before a Tuesday afternoon meeting of top policymakers from across the national security establishment, one official said. HuffPost interviewed multiple U.S. and foreign officials who were not authorized to speak on the record.

This last week, the level of concern in D.C. about a potential war on the Israel-Lebanon front has gone up three or four notches, said Randa Slim, a senior fellow at the Middle East Institute think tank.

Israels possible actions in Lebanon would be just the latest kindling for a major Mideast conflagration, following a string of attacks tied to Iran against U.S. troops in the region

On Sunday, a U.S. Navy warship and commercial vessels in a crucial global waterway near Yemen faced drone and missile strikes from an Iran-linked Yemeni armed group known as the Houthis that sparked an hours-long firefight, and on Wednesday an American destroyer shot down a Houthi drone. The Houthis have publicly said Israels moves in Gaza are motivating their assault, and the U.S. is now considering options for a show of force against the Houthis, officials say.

The Pentagon has documented dozens of attacks against American forces throughout the Middle East, including in Iraq and Syria, in recent weeks. The Syria and Iraq incidents were discussed at the Tuesday meeting, according to a U.S. official. On Friday, the U.S. Embassy in Baghdad faced a mortar attack .

And the source of much of the tension across the region the extremely high toll of the Gaza war, which Israel says has killed two civilians for every militant, for a total death toll of more than 16,000 so far is far from abating. Despite repeated calls for Israeli restraint from senior figures in the Biden administration, U.S. intelligence assesses the Israel Defense Forces are committed to business as usual, with only limited concern about civilian casualties, a U.S. official said, and there are suspicions the renewed campaign is actually bloodier than the previous offensive in northern Gaza.

Humanitarian organizations are ringing the alarm bell more than they ever have during the conflict in talking to the State Department, an official in the department said. Those aid groups are telling diplomats they may need to wind down their operations in Gaza given the heavy fighting, which would make the situation dramatically worse, the official said, on top of shortages of food and a rampant spread of disease among the 1.9 million Gazans forced out of their homes since Israel began its offensive in retaliation for an Oct. 7 attack by the Gaza-based group Hamas.