Civilians in the port city of al-Hodeidah will 'pay a terrible price' unless the warring parties act immediately to protect them, agencies say.
The Iran-backed Houthis are planting mines at an 'astonishingly high rate' according to a July report, with an estimated 500,000 mines laid since 2015.
The Iran-backed militia has prevented residents from leaving their homes in a bid to use them as human shields against advancing Yemeni troops.
The militia has resorted to forced recruitment of youth into its ranks prompting many to flee the province.
The goal of the programme is to return children conscripted by Iran-backed Houthi militias to schools, playgrounds and normal childhood activities, organisers say.
Some of the children kidnapped or recruited and then brainwashed, drugged and sent to the frontlines are as young as 8 years old, officials say.
Families fleeing the conflict around the Red Sea port have fled to other areas, including Sanaa, where some have found shelter in schools.
Displaced Syrians risk losing claim to land they own under two new laws passed this year that allow the government to seize private property.
Egyptian officials in Damascus say they are taking all necessary measures to help Egyptian citizens trapped in Syria return safely to Egypt.
Banned anti-personnel mines planted by the Iran-backed militia have left 814 people permanently disabled, Yemen's human rights minister said.