By Kristian Coates Ulrichsen, Rice University

When the longtime political chief of Hamas was assassinated in late July 2024, it didn't just leave the entire Middle East on edge. It also created a political headache in Qatar.

Batoul and her family have been scrambling to secure housing outside Beirut's southern suburbs where an Israeli strike killed a senior Hezbollah commander last week, but spiking demand has sent prices soaring.

Many in the southern suburbs -- a packed residential area known as Dahieh which is also a Hezbollah bastion -- have been trying to leave, fearing full-blown war between the Iran-backed group and Israel in the wake of the commander's killing.

As Iran threatens to respond to the suspected Israeli assassination of Hamas leader Ismail Haniyeh in Tehran, the regional militias that the Islamic Republic has armed for decades could play a role in any attack.

Here's a look at Iran's history of arming militias, its allies in the region and what part they could play.

The Iran-aligned "axis of resistance" against Israel and its allies have lost two major figures in less than 24 hours in attacks either blamed on or claimed by Israel.

Hamas political chief Ismail Haniyeh was killed on Wednesday in Tehran in a strike the group blamed on Israel, hours after top Hezbollah commander Fouad Shukur perished in an Israeli strike on southern Beirut.

By Asher Kaufman, University of Notre Dame

Israel's apparent assassinations of Fouad Shukur, Hezbollah's top military leader, in Beirut, and Hamas political leader Ismail Haniyeh, in Tehran, have raised again the specter of a regional war involving regional adversaries – one that could potentially drag the United States into the fray.

The killing in Tehran of Hamas political leader Ismail Haniyeh, which the Palestinian militant group has blamed on Israel, has exposed the depth of Israeli penetration inside the Islamic republic, analysts say.

Doha-based Haniyeh, who the day earlier had attended the inauguration of new Iranian President Masoud Pezeshkian, was killed in the early hours of Wednesday morning at a residence in northern Tehran, according to Iran's Revolutionary Guards.

A pair of strikes on militant leaders in Beirut and Tehran has escalated tensions in a region already on edge and adds to a long list of targeted killings attributed to Israel.

Hamas said Israel was behind the assassination of its supreme leader Ismail Haniyeh in Iran's capital, although there was no acknowledgement from Israel. And Israel claimed responsibility for a strike on Fouad Shukur, a top Hezbollah commander in Beirut, that the military said killed him.

By Mireille Rebeiz, Dickinson College

A missile strike that killed 12 children playing soccer in the Israeli-occupied Golan Heights on July 27, 2024, has prompted international concern that the Middle East conflict could expand into the disputed territory.

Two days after a rocket slammed into a soccer pitch in the Israel-controlled Golan Heights, killing 12 children, many questions remain about the attack on the Druze town of Majdal Shams.

Israel accused Hezbollah in Lebanon of deliberately targeting civilians, while Hezbollah quickly issued a rare denial of any responsibility for the attack.

After a deadly strike on civilians in the annexed Golan Heights, Israel has threatened retaliation against Lebanon's Hezbollah, accusing it of perpetrating the attack with an Iranian-made Falaq-1 rocket -- part of its wide-ranging arsenal.

Hezbollah has traded near-daily cross-border fire with Israel in support of Hamas since the Palestinian militant group's October 7 attack on southern Israel triggered war in the Gaza Strip.