The Saudi-led coalition backing Yemen's exiled government began an assault Wednesday on the port city of Hodeida, the main entry point for food in a country already teetering on the brink of famine.
The assault on the Red Sea port aims to drive out Iranian-aligned Shiite rebels known as Houthis, who have held Hodeida since 2015, and break the civil war's long stalemate. But it could set off a prolonged street-by-street battle that inflicts heavy casualties.
The fear is that a protracted fight could force a shutdown of Hodeida's port at a time when a halt in aid risks tipping millions into starvation. Some 70 percent of Yemen's food enters via the port, as well as the bulk of humanitarian aid and fuel supplies. Around two-thirds of the country's population of 27 million relies on aid and 8.4 million are already at risk of starving.
Before dawn Wednesday, convoys of vehicles appeared to be heading toward the rebel-held city as heavy gunfire rang out, according to videos posted on social media.
Saudi-owned satellite news channels and state media soon announced the battle had begun, citing military sources. They reported coalition airstrikes and shelling by naval ships as part of Operation "Golden Victory."
The initial battle plan appeared to involve a pincer movement. Some 2,000 troops who crossed the Red Sea from an Emirati naval base in the African nation of Eritrea landed west of the city with plans to seize Hodeida's port, Yemeni security officials said.
Emirati forces with Yemeni troops moved in from the south near Hodeida's airport, while others sought to cut off Houthi supply lines to the east, the officials said. They spoke on condition of anonymity as they weren't authorized to brief journalists.
Yemen's exiled government "has exhausted all peaceful and political means to remove the Houthi militia from the port of Hodeida," it said in a statement. "Liberation of the port of Hodeida is a milestone in our struggle to regain Yemen from the militias."
The Houthi-run Al Masirah satellite news channel later claimed rebel forces hit a Saudi coalition ship near Hodeida with two missiles. Houthi forces have fired missiles at ships previously.
The Saudi-led coalition did not immediately acknowledge the incident. The United States Navy's 5th Fleet, whose area of responsibility includes the Red Sea, referred questions to the Pentagon, which did not immediately respond to a request for comment.
Forces loyal to Yemen's exiled government and fighters led by Emirati troops had neared Hodeida in recent days. The port is some 90 miles southwest of Sanaa, Yemen's capital, which has been in Houthi hands since September 2014. The Saudi-led coalition entered the war in March 2015.
The United Nations and other aid groups already had pulled their international staff from Hodeida ahead of the assault.
The port remains open, with supplies arriving. Several ships have arrived in recent days, including oil tankers, and there has been no word from the coalition or UN to stop work, according to a senior port official, who spoke on condition of anonymity because he was not authorized to talk to the press.
Robert Mardini, the regional director for the Red Cross, said the push on Hodeida "is likely to exacerbate an already catastrophic humanitarian situation in Yemen. The population has already been weakened to extreme levels," he added.
David Miliband, the head of the International Rescue Committee, called the offensive "an attack on the political and diplomatic process to bring peace to Yemen." He said the UN Security Council must act to secure a cease-fire before the people of Hodeida "suffer the same fate as those in Aleppo, Mosul, or Raqqa."
Over 10,000 people have been killed in Yemen's civil war, which has displaced 2 million more and helped spawn a cholera epidemic. Saudi-led airstrikes that killed large numbers of civilians and damaged vital infrastructure. Meanwhile, the UN and Western nations say Iran has supplied the Houthis with weapons from assault rifles up to the ballistic missiles they have fired deep into Saudi Arabia, including at the capital, Riyadh.
The coalition has blocked most ports, letting supplies into Hodeida in coordination with the UN. The air campaign and fighting have disrupted other supply lines, causing an economic crisis that makes food too expensive for many to afford.
The UN says some 600,000 people live in and around Hodeida, and "as many as 250,000 people may lose everything – even their lives" in the assault. Already, Yemeni security officials said some were fleeing the fighting.
"We hear sounds of explosions. We are concerned about missiles and shells. Some workers have left to their villages for fear of the war," said Mohammed, a Hodeida resident who gave only his first name for fear of reprisals.
Aid workers had similar worries.
"We have had more than 30 airstrikes within 30 minutes this morning around the city. Some civilians are entrapped, others forced from their homes," said Jolien Veldwijk, the acting country director of the aid group CARE International, which works in Hodeida. "We thought it could not get any worse, but unfortunately we were wrong."
The new UN envoy to Yemen, Martin Griffiths, tweeted that he was "extremely concerned" by the violence, calling on all parties to exercise restraint. Mr. Griffiths' recent appointment as envoy and his push for new negotiations may have encouraged the Saudi-led coalition to strengthen its hand ahead of any peace talks with the Houthis.
The attack comes as Washington has been focused on President Trump's recent summit with North Korean leader Kim Jong-un. The US has been offering targeting information to the Saudi-led coalition, as well as refueling their warplanes, though its role in Wednesday's assault wasn't immediately clear.
This story was reported by The Associated Press.