As the result of the most intense battles in the nearly six-year Syrian conflict, "at least 96 children have been killed and 223 have been injured in eastern Aleppo since Friday," according to a statement from UNICEF.

Since the start of the week, Syrian planes and Russian jets allegedly have dropped more than 1,700 bombs on the eastern half of Aleppo, which is controlled by rebel forces, reports The Guardian. As airstrikes intensified this week, a senior Iranian general, Major General Yahya Rahim Safavi, told The Guardian ground forces he commands gathered and supplied information to the Russian air force with the locations of their targets. According to Reuters, the governments of Russia and Syria claim they are only targeting rebel forces.

But the high civilian death toll tells a different story.

“The children of Aleppo are trapped in a living nightmare,” said UNICEF Deputy Executive Director Justin Forsyth in a statement. “There are no words left to describe the suffering they are experiencing.”

UNICEF describes the remaining health care system in eastern Aleppo, as "crumbling," with roughly 30 doctors left, barely any equipment or emergency medicine, and a rising number of trauma cases. Additionally, "a doctor on the ground told UNICEF that children with low chances of survival are too often left to die due to limited capacity and supplies."

Forsyth noted, “Nothing can justify such assaults on children and such total disregard for human life. The suffering – and the shock among children – is definitely the worst we have seen."

America has seen the conflict's effect on children through shocking images, most notably of Omran Daqneesh and Alan Kurdi.

The death toll of children is part of a larger number of civilian casualties, which humanitarian groups are condemning, along with other human rights violations.

"Obviously, the humanitarian situation inside east Aleppo is going from bad to worse,” David Swanson, spokesman for the U.N. Office for the Coordination of Humanitarian Affairs, told ABC News. “The situation even before this recent upsurge in violence was dire with many people lacking access to food, health, shelter and water. Between 250,000 and 275,000 people are now living without proper access to running drinking water. Right now, 20 trucks are standby and ready to enter as soon as the latest round of violence improves.”

EU foreign affairs chief Federica Mogherini has also called the air bombardment in Aleppo, a "massacre" and stated European governments were considering their response, reports Reuters. As for how Washington will respond, U.S. officials told Reuters "they are considering tougher responses to the Russian-backed Syrian government assault, including military options, although they have described the range of possible responses as limited and say risky measures like air strikes on Syrian targets or sending U.S. jets to escort aid are unlikely."

In 2011, the Syrian civil war began when President Bashar Al-Assad violently used force to crush dissent among hundreds of thousands of pro-democracy protesters who took to the streets to demonstrate against civil rights abuses. Since then, violence escalated, sectarian conflict emerged, and rebel brigades were formed to fight government forces, with the governments of Syria, Russia, and the United States all launching air strikes on various rebel forces on the ground, resulting in the death and displacement of thousands of civilians in the process.

Eastern Aleppo, which was captured by rebel groups in cooperation with Al-Qaida forces now referring to themselves as Jabhat Fateh Al-Sham, is one of the key flashpoints in the Syrian conflict. Beyond Aleppo's status as Syria's largest city and a financial capital, the eastern half of the city also represents the largest victory of the entire conflict for rebel groups. As such, recapturing eastern Aleppo remains a focus of the Assad regime.

The death toll from the war in Syria is at least 470,000, according to a report released in February.

In addition to airstrikes by the governments of Syria and Russia, the U.S. has conducted 5,068 airstrikes in Syria since a U.S.-led campaign against ISIS began in 2014, according to the U.S. Department of Defense. The monitoring group Airwars reports that U.S. airstrikes have resulted in the deaths of at least 850 civilians in Syria since they began bombing.