The UN has identified conflict as the "root cause" of Yemen's crises. Tens of thousands of people have been killed since the war erupted in 2014, when Shiite Houthi rebels launched a campaign to capture the capital, Sanaa. In March 2015, a Saudi-led coalition launched a deadly campaign against the rebels, one that has been widely criticized by human rights groups for its high civilian death toll.

The conflict has prevented humanitarian aid from reaching large parts of the civilian population, resulting in more than two-thirds of the country's 28 million people being classified as "food insecure." Nearly 3 million children and pregnant or nursing women are acutely malnourished, according to the UN World Food Program.

More than 3 million people have been displaced by conflict, including marginalized communities such as the "Muhammasheen," a minority tribe that originally migrated from Africa. Despite the civil war, many flee conflict in Somalia and head to Yemen, marking the convergence of two major migration crises in the Middle East nation. Yemen hosts around 250,000 Somali refugees, according to UNHCR.

The number of suspected cholera cases has exceeded more than 2 million and least 3,700 people have died from the waterborne bacterial infection in Yemen since October 2019, said the WHO. Although cholera can be easily treated, it can kill within hours when untreated.

In Yemen, violence goes beyond civil conflict: It is considered a strategic front in the war on terrorism. The country serves as the operational base for al-Qaida in the Arabian Peninsula, dubbed the "most dangerous" terrorist group before the rise of the "Islamic State." The US routinely uses drones to target al-Qaida leadership. However, civilians have often been killed in the operations.

In a country paralyzed by conflict, children are one of the most at-risk groups in Yemen. More than 12 million children require humanitarian aid, according to the UN humanitarian coordination agency. The country's education system is "on the brink of collapse," while children are dying of "preventable causes like malnutrition, diarrhea and respiratory tract infections," according to the agency.

Despite several attempts at UN-backed peace talks, the conflict continues to rage on. Saudi Arabia has vowed to continue supporting the internationally recognized government of Yemeni President Abed Rabbo Mansour Hadi. On the other hand, Houthi rebels have demanded the formation of a unity government in order to move forward on a political solution. A peace deal, however, remains elusive.

These girls are attending a class at their school in the Yemeni port city of Hedeidah despite the fact that a wall has been almost completely taken out by a Saudi-led air strike. The country has been enmeshed in a bloody civil war for three years now, and the conflict shows no sign of ending. Saudi Arabia has led a coalition fighting Iran-backed Houthi rebels since 2015.

Syria is another country in the Middle East wracked by civil conflict, with millions displaced and hundreds of thousands killed. Some of the displaced children are seen here being taught in a barn for lack of school buildings in the rebel-held area of Daraa in southern Syria. Chairs are also in short supply, meaning several of the children have been forced to sit on stones instead.

Although Iran and Russia, which both back the regime of Syrian President Bashar al-Assad, made a deal with rebel backer Turkey to make Eastern Ghouta a "de-escalation zone" from July, the agreement has been repeatedly violated. This school in the Eastern Ghouta village of Hamouria did not escape damage, and humanitarian workers have warned of a dire situation inside the enclave.

Syrian children are seen here attending classes in improvised conditions in a rebel-held area of the southern city of Daraa. Although many countries are determined that children in Syria should not become a "lost generation" for lack of schooling, the war is making it difficult and sometimes impossible for lessons to continue.

This wall at a school in the Syrian village of Hazima, north of Raqqa, is full of bullet holes from the war. The extremist group "Islamic State" closed the school and many others in northern Syria when it took over the region in 2014. Now it has been driven out, children can go back to learning normal subjects instead of the extremist propaganda taught by the hardline Islamists.

"Where do the children play?" British singer Yusuf Islam, commonly known by his former stage name of Cat Stevens, once asked in a song. These children have found their playground in this damaged school in al-Saflaniyeh in eastern Aleppo province. But one can only wish they had nicer, and safer, surroundings for their games.