Outrage over Saudi-led coalition 'horse massacre' in Yemen's capital
Around 70 Arabian horses and one civilian died in the attack in the strike on a stable at a military college in Sanaa, the rebels’ Al Masirah news channel reported.
Graphic images emerged online shortly after, showing dead and wounded horses strewn across the area.
The attack prompted Yemenis and animal rights activists to call for greater accountability in the conflict, where more than 100,000 have been killed - half of them civilians.
The operation was aimed at destroying "legitimate military targets" including Houthi ballistic capabilities which "threaten civilian lives", the coalition said in a statement released by the official Saudi Press Agency.
Residents in Sanaa reported multiple explosions after the coalition's bombing campaign began.
The Houthi-run Al-Masirah television reported at least 19 air strikes on a number of targets in Sanaa, including military bases and the military academy, where the horses were sheltered.
The operation comes after Saudi air defences intercepted Houthi ballistic missiles over Riyadh and the border city of Jizan, late Saturday.
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The attacks left two civilians wounded in Riyadh, which is under a 15-hour curfew to limit the spread of coronavirus, according to Saudi state media.
It was the first major assault on Saudi Arabia since Houthi rebels last September offered to halt attacks on the kingdom, after devastating twin strikes on Saudi oil installations.
A Houthi spokesman said the rebels struck "sensitive targets" in Riyadh with long-range Zolfaghar missiles and Sammad-3 drones. The rebels also claimed to have hit "economic and military targets" in the border regions of Jizan, Najran and Asir.
Information Minister Moammer al-Eryani slammed the attack in a tweet posted on Twitter, saying it confirmed the "continued flow of Iranian weapons" to the Houthi militias.
"This militia lives only on wars and doesn't understand language of peace," he said.
Fighting has also escalated between the Houthis and Riyadh-backed Yemeni troops around the strategic northern districts of Al-Jawf and Marib.
The rebels stormed a key government military camp in Al-Jawf after heavy clashes on Monday, according to Yemeni military sources.
The warring sides had earlier shown an interest in de-escalation, with a Saudi official saying in November that Riyadh had an "open channel" with the rebels to end the war.
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But those efforts seem to have unravelled and observers believe the rebels may have used the lull to bolster their military capabilities.
Riyadh had expected a quick victory when it led a multi-billion dollar intervention in 2015 to oust the Houthi rebels, under a newly assertive foreign policy led by Crown Prince Mohammed bin Salman.
But the costly intervention has failed to uproot the rebels from their northern strongholds, while pushing the Arab world's poorest nation into a humanitarian crisis. More than 100,000 have died since the Saudi-led military intervention in March 2015.