Saudi-led warplanes pounded military installations in Yemen on Friday in a campaign aimed at halting the advance of Shiite Muslim rebels and securing the return of President Abdu Rabu Mansour Hadi, who has fled the country.
Some of the targets are located in or near residential areas and there have been reports of civilian casualties. As many as 20 people were killed when a market was hit in the region of Saada, in the Houthi rebels' northern heartland, local authorities said.
Brig. Gen. Ahmed Asiri, a spokesman for the campaign dubbed "Operation Decisive Storm," told reporters in Saudi Arabia that the airstrikes were destroying rebel-held air defense systems, bases, aircraft and missiles.
He said there were no immediate plans for a ground assault, but the coalition assembled by the Saudis was ready "to deter any aggression of any kind."
Egyptian security officials told the Associated Press on Thursday that troops would invade from Saudi Arabia and from ships off the coast after Yemen's rebel-held defenses had been weakened.
Yemen's foreign minister, Riad Yassin, told Saudi-owned Al Arabiya television that he expected the campaign to be over in a matter of days and that Hadi would return after attending a weekend summit in Egypt.
He said one of the goals was to prevent Tehran from providing weapons and training to the rebels, saying he has seen proof that members of Iran's Revolutionary Guard Corps were in Yemen.
Both Iran and the rebels have denied such accusations, although they acknowledge that Tehran has provided diplomatic and logistic support.
The Saudi-led campaign has opened a new front in the rivalry between the region's main Sunni Muslim power, Saudi Arabia, and Shiite-led Iran.
The Saudis and their allies view the Houthi uprising as an attempt by Iran to put into power a proxy in Yemen, which shares a long, porous border with Saudi Arabia to the north.
During Friday prayers in the Saudi capital, Riyadh, preachers railed against the Houthis and their Iranian allies, describing the campaign as a religious obligation, news reports said.
In Tehran, Friday prayer leader Ayatollah Kazem Sadeghi condemned the "foreign military interference in Yemen" and offered condolences for the victims. But he stopped short of calling for military aid to be sent to the Houthis.
Regional experts say Iran's leaders don't want to jeopardize sensitive talks with the United States and other world powers over Tehran's nuclear program.
Hadi has been a key ally of the U.S. in the fight against Al Qaeda's Yemen branch, the terrorist network's most dangerous affiliate. The United States is providing logistic and intelligence support to the Saudi-led campaign but is not taking direct military action in Yemen, officials say.
In a televised address late Thursday, the Houthi leader, Abdul-Malak Houthi, vowed that Yemenis would rise up against the Saudi-led campaign and defend their land.
Despite the airstrikes, Houthi forces continued to press south Friday, according to local reports.
Residents described fierce clashes between the fighters and forces loyal to Hadi in the southern port city of Aden, where the president sought refuge after Houthi rebels took over the capital, Sana.
Hadi reportedly fled the city by boat Wednesday, arriving in the Saudi capital the following day. On Friday, he continued to the Egyptian Red Sea resort of Sharm el Sheik, where an Arab summit is scheduled to begin Saturday.
In Sana, residents endured a second day of thundering bombardments Friday.
Mohammed Dubai said his children were scared; the young ones were crying. "You cannot tell or know what is happening exactly," he said.
Frustration was building in the city, where many families have fled neighborhoods that are close to military installations.
Murad Barakat said he opposed the Houthis but couldn't support a president who brought foreign troops into Yemen to destroy the country's defenses.
"I was against the Houthis with every meaning of the word, but now it's about our dignity," he said. "This attack was against all of us, north, south, east and west. "So if we don't show our solidarity now, then we are not even worth the missiles the Saudi keeps shelling us with."
Friday's targets included bases occupied by Republican Guard members loyal to Hadi's ousted predecessor, President Ali Abdullah Saleh, who has struck an alliance with the Houthi movement.
Airstrikes were also reported at Al Anad air base in the south, which had until recently been used by U.S. counter-terrorism forces. Rebel fighters seized the base Wednesday as they advanced toward Aden.
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