Saudi-led warplanes intensified their air strikes against Yemeni rebels in the capital Wednesday, fueling panic as political efforts to end a war that has displaced half a million people foundered.
The Arab coalition has waged an air campaign against the Iran-backed Shiite rebels since March 26 in an effort to restore the authority of exiled President Abed Rabbo Mansour Hadi, who fled to Riyadh.
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After a five-day humanitarian ceasefire expired at the weekend, the Saudi-led coalition resumed bombing several cities including the capital, accusing the rebels of having violated the truce.
Witnesses in rebel-held Sanaa described Wednesday's bombing as the most violent so far, prompting residents to flee.
Loud explosions ripped through Sanaa until the early hours as warplanes targeted rebel-held arms depots for a second straight night, residents said.
"Sanaa witnessed during the night the most violent raids since the start of the bombing" by coalition warplanes, said Saleh Moqbel, one resident of the capital's Old City.
Strikes since Tuesday have hit arms depots in hills overlooking Sanaa as well as the rebel-held presidential complex, with explosions lighting up the skies, residents said.
The raids prompted many families to flee residential areas surrounding the hills and seek refuge elsewhere in the city, witnesses said.
Political hopes dashed
"Some of these families were hosted by relatives, while others were forced to rent shelters, including garages, to spend the night," said Hasan al-Amudi, who lives in central Sanaa.
Hotel employee Ahmed Melhi said that "since the start of the crisis the hotel had been completely empty. But today it is flooded with people from the Noqum and Fajj Attan neighbourhoods."
In the central province of Ibb, witnesses reported seven coalition air strikes, mostly targeting a pro-rebel army camp.
Other strikes targeted the rebel stronghold of Amran province in north Yemen and Abyan province in the south.
Hopes faded for a speedy political breakthrough in the two-month conflict with a UN-sponsored peace conference originally set for next week put on hold because of the resumption in fighting.
A conference of Yemeni political factions held in Riyadh, meanwhile, vowed support for "resistance" forces battling rebels.
The Houthi rebels have allied with troops loyal to former president Ali Abdullah Saleh and have been locked in deadly clashes with pro-Hadi fighters across Yemen.
Iran, a key ally of the Houthis, has demanded an end to the Saudi-led bombing and said Riyadh was not a suitable location for peace talks.
The conflict has caused humanitarian chaos, with the United Nations saying more than half a million people have been displaced.
Iran aid ship
An Iranian aid ship bound for Yemen in defiance of US warnings has entered the Gulf of Aden and is expected to reach port on Thursday.
Its mission has been overshadowed by US calls for it to head to a UN emergency relief hub in Djibouti instead of docking in the Yemeni port of Hodeida.
Iran says that it had made all the appropriate arrangements with the relevant UN authorities for the aid shipment.
The coalition has imposed an air and sea blockade of Yemen.
But Khaled al-Shayef, director of the rebel-held Sanaa airport, said it "has not been hit by any raids since the start of the truce" that ended late on Sunday.
A passenger plane from national carrier Yemenia landed at Sanaa at midday on Wednesday, carrying some 200 Yemenis from Cairo, Shayef said.
Two more such flights were expected later in the day.
International aid agencies had repeatedly warned that the coalition bombing of impoverished Yemen's airports was obstructing aid deliveries aimed at easing a "catastrophic" humanitarian situation.
Citing Yemen's health services, the United Nations said that as of May 15, some 1,850 people had been killed and 7,394 wounded in the violence in Yemen. Another 545,000 had been displaced.
The UN refugee agency said its assessments on the ground during the five-day ceasefire had "exposed enormous difficulties for thousands of civilians displaced by conflict."
About 7,000 refugees have fled to Somalia — mostly Somalis returning home — since the air war began, Nicholas Kay, the UN special representative for Somalia, said on Tuesday.