GENEVA, April 9 (Xinhua) -- Sunday's explosion in the Yemeni capital of Sanaa had killed 14 children and critically injured 16 others, most of them aged under nine, a United Nations Children's Fund (UNICEF) spokesperson said on Tuesday.

"This is what UNICEF was able to verify, with the actual number of children killed and injured likely to increase," Christophe Boulierac, UNICEF Geneva spokesperson, said at a UN briefing here.

In Sanaa, a medic told Xinhua that the death toll from Sunday's explosion increased to 15, including seven schoolgirls, while more than 100 others mostly female students were wounded.

"The death toll has increased from 13 to 15, including seven schoolgirls," the medic told Xinhua on condition of anonymity.

Sunday's explosion occurred in a warehouse near two schools in Sawan quarter, the most densely populated neighborhood, east of Sanaa.

"The critically injured children, many of whom are fighting for their lives, are now in hospitals in Sanaa," Boulierac said, reading a statement from Geert Cappelaere, the agency's regional director for the Middle East and North Africa.

More than 400 children have been killed and seriously injured since the beginning of 2019, including an attack in Hajjah near the Red Sea port city of Hodeidah on March 9 in which 12 children were killed, according to UNICEF.

UNICEF said 2,672 have been killed and 4,371 injured in Yemen since the conflict escalation in 2014.

Boulierac said Monday's blast is another reminder that even schools are not safe in Yemen. One in five schools can no longer be used as a direct result of the conflict.

UNICEF said that for more than 2 million children in Yemen today, going to school is a distant dream and that Monday's blast may further discourage parents from sending their children to school.

A civil war has plagued Yemen since late 2014 after Houthi rebels revolted against the government of President Abd-Rabbu Mansour Hadi.