The Houthi movement in Yemen mourns the death of Hezbollah chief Hassan Nasrallah, their ally in an Iran-backed alliance opposing Israel. Hezbollah confirmed Nasrallah's killing after an Israeli airstrike in Beirut. Both Hezbollah and the Houthis are part of the Axis of Resistance, an alliance built up over years of Iranian support against Israel and US influence in the Middle East. The Houthis have launched repeated drone and missile strikes on ships they say are affiliated to Israel, as well as targeting central Israel for the first time.