Tens of thousands protested in Iranian cities and in the rebel-held Yemeni capital on Friday to condemn Israeli attacks on Lebanon and Gaza, AFP journalists and state media reported.
The demonstrations in Tehran and other Iranian cities were responding to a call by authorities on Wednesday to demonstrate in support of the Iran-backed Hezbollah movement in Lebanon "and to condemn the barbaric crimes of the Zionist regime in Palestine," the official IRNA news agency said.
Hezbollah is part of the "axis of resistance," Iran-aligned armed groups across the Middle East that have targeted Israel, and also US forces, in support of Palestinian militant group Hamas.
The alliance also includes Yemen's Huthi rebels who organised a demonstration by tens of thousands in the capital Sanaa on Friday a day after firing a missile at Israel.
In Tehran after Friday prayers, a protest took place around Enghelab Square in the city centre, an AFP journalist said.
Demonstrators carried portraits of Hezbollah chief Hassan Nasrallah as well as Palestinian and Hezbollah flags.
"Israel is destroyed. Lebanon is victorious," they chanted, deploring "a bloodbath in Lebanon."
Protesters also burned Israeli and US flags.
State television aired footage of other demonstrations in Semnan, Qom, Kashan, Kermanshah, Shiraz and Bandar Abbas.
In Sanaa, which has been held by the Iran-backed Huthis for a decade, tens of thousands of chanting protesters gathered, many waving rifles and placards.
"We say to our brothers in Lebanon that you will be victorious, God willing,” said Huthi supporter Mortada al-Mutawkil. “This war is not the first nor the last with the Israeli enemy, but God willing it will be more painful for Israel than the 2006 war.”
Another protester, Mohammed Mushki, said: "No matter how long the war lasts and no matter how big it is, we are on their side, all the Yemeni people, on the side of the Lebanese and Palestinian people until victory, God willing."
In Bahrain, which is an Israeli ally and keeps a tight rein on demonstrations, two protests denounced the war in Gaza and bombing campaign on Lebanon.
Several hundred people marched in a village north of Manama, voicing solidarity with Gaza and Lebanon, and in the capital scores of people raised Palestinian and Lebanese flags and called for an end to ties with Israel.
“The people demand an end to normalisation,” the protesters chanted.
Hamas attacked Israel on October 7, triggering a war with Israel and near-daily cross-border fire from Hezbollah in Lebanon against Israel, which has hit back.
Those exchanges have intensified dramatically over the past week. Israeli raids on Lebanon since Monday have killed hundreds in the deadliest violence since Lebanon's 1975-1990 civil war.
As the violence escalates, analysts say Iran is walking a tightrope by trying to support Hezbollah without getting dragged into a full-blown conflict and playing into its enemy's hands.