(CNN)Health workers scramble to pulled lifeless bodies out from under mounds of rubble after airstrikes reportedly hit and killed 82 civilians in the eastern part of the Syrian province of Deir Ezzor, a human rights groups said.
Airstrikes in Syria kill scores of civilians
Three air attacks targeted heavily crowded areas, including a mosque during prayer time on Saturday, in the town of al-Quriyah, UNICEF said in a statement. The U.N. agency said that 25 children were among the dead.
Deir Ezzor city, the provincial capital, has been a hotbed of conflict since ISIS militants captured the northern suburbs in January. The city has been a critical junction for ISIS, with roads east and south toward Iraq and west to areas it controls in Homs province, including Palmyra.
It is also surrounded by some of ISIS' most valuable oilfields, which have been intensively targeted by both U.S. and Russian airpower in recent months.
"It is unclear whether these airstrikes were carried out by Russian or Syrian warplanes," Rami Abdul Rahman, the founder of the Syrian Observatory for Human Rights (SOHR), a London-based organization that monitors the war in Syria, told CNN on Monday.
In the past, activist and aid groups have accused Russian and Syrian forces for similar airstrikes in the war torn country.
Last year, the U.S. State Department strongly criticized Russia for what the department called "indiscriminate attacks" that have reportedly caused hundreds of civilians casualties since Moscow began flexing its military might in the war torn country.
Russia has repeatedly denying such accusations, saying the aim of its military operations inside Syria is to defeat "terrorist targets."
Meanwhile, ISIS released a new video depicting the gruesome execution of five Syrian activists from Deir Ezzor.
The militant group claims the executions were carried out on charges of "acting against the Islamic state, communicating with outside parties and receiving funds, and other charges."
While the onslaught of violence is being met with resistance, more than 250,000 people have been killed, 1 million injured and millions of refugees and internally displaced people, since the country's civil strife began in 2011, according to the United Nations.
The critical concern for aid workers is that attacks on children in Syria "are becoming commonplace with callous disregard for the lives of children," UNICEF said.