At least 23 killed in strike on dairy factory in Yemen

At least 23 people were killed overnight on Tuesday when a blast rocked a dairy factory in Yemen's Red Sea port of Hudayda, medical sources told Reuters. 

The true death toll could be even higher, with the provincial governor telling AFP that 37 have been killed. 

The incident appears to be one of the deadliest in terms of civilian casualties since the Saudi-led coalition began its aerial bombardment campaign in Yemen last Wednesday. It was not immediately clear if factory was bombed from the air by the coalition or hit by Houthis or other forces. 

Fierce clashes were also reported on the northern border with Saudi Arabia late on Tuesday, with Reuters reporting that it was the heaviest exchange of cross-border fire between the two countries since the start of the campaign.

Residents and tribal sources in north Yemen told Reuters that artillery and rocket exchanges were occurring on several stretches of the border. Explosions and heavy gunfire were heard with Saudi helicopters flying overhead, the sources said.

The Saudis claim to have mobilised 150,000 troops, Saudi-owned al-Arabya reported last week, and have not ruled out a ground invasion if necessary.  

Saudi Arabia and other Sunni Muslim states who have joined the campaign say they are trying to stop the Houthis and former president Ali Abdullah Saleh from taking over the country.

However, despite seven days of bombing, they have so far not managed to reverse the Houthi tide or reinstate President Abd-Rabbuh Mansour Hadi who fled to Saudi Arabia late last month.

UN Secretary-General Ban Ki-moon on Tuesday expressed concern about civilian casualties resulting from Saudi-led military operations in Yemen.

"The Secretary-General reminds all parties involved in military operations in Yemen of their obligations under international humanitarian law to ensure the protection of civilians," according to a statement issued from Ban's office.

Ban singled out Monday's strike on a refugee camp in the west of Yemen, as well as recent reported attacks against several hospitals in the south of the country, the statement said.

The International Organisation for Migration, which had workers in the camp, reported that 40 people had been killed.

The camp houses displaced families from Yemen's northern Saada province who fled due to earlier fighting between the Houthis and government forces.

UNICEF meanwhile stressed that at least 62 children have been killed and 30 injured in Yemen over the past week.

"Children are in desperate need of protection, and all parties to the conflict should do all in their power to keep children safe," said UNICEF's representative for Yemen, Julien Harneis said on Tuesday.

The UN also warned that the already fragile health system had begun to fail in parts of the country, with Aden particularly hard hit by the fighting.

Al-Khadher Laswar, a Health Ministry official in Aden, described the situation as “miserable”.                                                                                

“The ambulances are only used to transport the dead,” he told the New York Times, adding that at least 88 people had been killed over the last six days in the city alone.

The United Nations earlier pulled its last remaining 13 foreign employees from Yemen, while its peace envoy, Moroccan diplomat Jamal Benomar, relocated to Jordan to try to revive negotiations.

"It's difficult in a time of war to get negotiations going, but it's precisely crucial to do so at that very time," UN spokesman Farhan Haq said.

"We need to get the fighting stopped and we need to get everything back on track."

The UN said Tuesday that at least 93 civilians had been killed and 364 injured since the nearly week-old Saudi-led air campaign began.