The assassination of Hamas leader Ismail Haniyeh in Tehran has raised alarms over the potential for escalating conflict in the Middle East, with the White House expressing concerns about a wider war. While U.S. officials work towards a ceasefire to mitigate ongoing violence in Gaza, the killing has complicated peace efforts and prompted threats of retaliation from Hamas and Iran. Israeli Prime Minister Benjamin Netanyahu's government has not officially claimed responsibility for the attack, but tensions are heightened after Israel also targeted a Hezbollah commander in Beirut shortly before Haniyeh's assassination. Various regional actors, including Iraqi factions, condemned the killing as a violation of international law and a threat to stability, vowing to respond aggressively. The assassination has been described by Hamas as a grave escalation, and Iran has declared national mourning while accusing the U.S. of complicity in the violence. Overall, the incident appears to be a significant turning point that could destabilize an already fragile regional situation.