CAIRO (AP) — Artillery fire killed at least 11 civilians, including four children, near Yemen’s strategic port city of Hodeida amid that country's grinding war, an international charity said Monday.

Yemen's internationally recognized government blamed the Iranian-backed Houthi rebels for the attack. A spokesman for the Houthis did not immediately respond to a request for comment.

Save the Children said the attack took place Sunday when shells hit home in the town of Durayhimi, just south of Hodeida, which handles about 70% of Yemen’s commercial and humanitarian imports. The shelling wounded 10 others.

“It’s appalling to witness more and more children losing their lives in their own houses, where they supposed to feel safe, play and study,” said Xavier Joubert Save the Children’s Yemen director.

The war in Yemen erupted in 2014, when the Houthis seized the capital and much of the country’s north. A Saudi-led coalition, determined to restore the authority of President Abed Rabbo Mansour Hadi’s government, launched a sweeping military intervention months later.

More than 600 civilians have been killed or wounded in Hodeida in the first nine months of 2020, according to Save the Children.

Sunday’s attack came just two weeks before the second anniversary of a cease-fire aimed at ending fighting in Hodeida. That deal, inked in December 2018 in Sweden and seen as an important first step toward ending the conflict, was never fully implemented

The head of the U.N. mission to Hodeida, retired Gen. Abhijit Guha, urged both sides to adhere to the 2018 U.N.-brokered agreement.

“Now is the time to hold fire and stop a cycle of military escalations that will worsen the dire humanitarian situation on the ground,” Guha said in statement.

Fierce clashes in Hodeida last month killed more than 52 people and wounded around 70 others, including over two dozen civilians. It was the heaviest bout of violence in months in the contested city.