emen's Houthi rebels seized control of the strategic Red Sea port city of Mokha on Thursday and were advancing towards the Bab al-Mandab strait, a Yemeni military source told AFP.

Witnesses told AFP they saw rebel forces entering the city while chanting "death to America, death to Israel".

Israel opened its first embassy in Slovenia on Wednesday, boosting relations with the small European Union nation even as ties sour with some longtime allies over its policy on illegal settlements in the occupied West Bank.

Israeli Foreign Minister Gideon Saar travelled to Ljubljana, Slovenia's capital, for the occasion that asserts a shift in Slovenia's policy toward Israel under the current right-wing Prime Minister Janez Jansa.

An Israeli strike killed at least four people in northern Gaza.

Two children were among the dead after Israel carried out a new strike in the northern Gaza community of Beit Lahiya, according to Shifa hospital, where the bodies were taken.

Yemen's Houthi rebels reported about 40 airstrikes launched by Saudi forces on Thursday in a fresh salvo following attacks by the Iran-backed group against the kingdom.

"The Saudi enemy's air force conducted around 40 strikes in recent hours in the governorates of Taiz, Hodeida, Al-Jawf and Marib," Houthi news agency Saba said.

An explosion at an arms depot in Syria's northwestern Idlib province killed 14 people on Wednesday, the local health department said, without specifying the cause of the blast.

"The toll from the explosion in a temporary storage for collecting weapons and war remnants near the city of Sarmada... registered 14 killed and 11 injured in a preliminary count," the Idlib health department said.

Rescuers dug through the rubble of a Houthi-run prison that was hit in an airstrike in northern Yemen earlier this week, even as the Saudi-led coalition renewed its attacks on rebel areas Wednesday. Rescuers recovered four bodies, raising the death toll at the prison to 23 people, the Houthis said.

The prison collapsed on Monday after it was hit when the coalition targeted the strategic city of Hazm in the northern Jawf province, which in turn prompted the Houthis to launch a wave of missile and drone strikes on southern Saudi Arabia that wounded 73.

Iran's foreign ministry on Wednesday strongly condemned U.S. strikes on its oil tankers, describing the attacks the previous day as a threat to regional security.

"The aggressive actions by the United States against Iranian commercial vessels not only increase the dangers of tensions in the region but are also considered an overt threat to regional and international peace and security," the ministry said in a statement, adding that Iranian forces had targeted U.S. military facilities in the region in "self-defense".

The sun set over this southern Iranian city, and Heydar Sadeghi was where he can be found almost every evening: on a bench next to the shattered remains of his grandson's school. His face was soaked with tears.

A banner strung around the rubble showed the faces of children and teachers killed here by an American airstrike on Feb. 28, the first day of the war on Iran. Among them are Sadeghi's 11-year-old grandson Hami and the boy's mother, Neda Salehizadeh.

In July, Saudi Arabia and the United States bombed Iran-backed militias in Iraq after blaming them for drone attacks on Saudi oil facilities that had been claimed by Yemen's Houthi rebels, another Iranian ally.

Now, regional officials tell The Associated Press that the Houthis helped the Iraqi militias plan and execute the two-day swarm attack, showing a new level of coordination.

Yemen's Houthi rebels reported dozens of Saudi airstrikes on Wednesday as daily attacks continued in a conflict that has reignited during the Middle East war, with hundreds of people killed in fighting near the Red Sea.

More than 40 attacks targeted several regions including the flashpoint areas of Taiz and Hodeida, the scene of fierce clashes between the Houthis and Saudi-backed government, the rebels said.