Warplanes dropped missiles apparently targeting a house occupied by a senior rebel commander, witnesses said. The missiles did not explode but their impact flattened at least three houses and caused cracks in surrounding buildings which are cemented to each other, leaving large sections of the district at risk of collapse.
Online activists posted pictures from the damaged portion of the city, next to men digging for survivors from under the debris. Others circulated pictures from before the destruction to show the scale of damage to the complex of houses occupying a district in the Old City known as al-Qasimi - one of the most popular and historic tourist attractions in the city.
In a statement from UNESCO, the agency's general director condemned the attack targeting "the world's oldest jewels of Islamic urban landscape" and expressing sorrow for the loss of lives.
"I am shocked by the images of these magnificent many- storied tower-houses and serene gardens reduced to rubble," Irina Bokova said in the statement and urged the warring parties to preserve the heritage of Yemen which "bears the soul of the Yemeni people" and "belongs to all humankind."
UNESCO said that since the beginning of the conflict, several historic monuments across Yemen have suffered damage. It said that on June 9, the Ottoman era al-Owrdhi historical compound, outside the walls of the Old City, was severely damaged.