Definition: In this task, you will be presented with a passage and have to answer a question based on your understanding of the events inferred from the passage. Try to find the best answer that is most likely to fill in "_". Note that the URLs in the text have been replaced with [Link].
Input: (CNN) Around 3,800 civilians, almost a quarter of them children, have been killed in Russian airstrikes in Syria in the year since Russia began its air campaign there, according to a UK-based monitoring group. The Syrian Observatory of Human Rights released the stark figures to mark the first anniversary of Russia's direct intervention in support of Syrian President Bashar al-Assad's forces. According to figures collated by the group, Russian airstrikes killed 2,337 men, 906 children and 561 women in the past year. During the same period, it said, Russian warplanes killed 2,746 ISIS fighters, along with 2,814 rebels. CNN cannot independently confirm the figures.Russian strikes have "increased the bloodshed of the Syrian people," group saysUN official denounces Security Council for humanitarian disaster in Syria 
 Question:The activist group's grim toll comes as rebel-held districts of Aleppo reel from an intense weeklong aerial bombardment by Syrian and Russian warplanes while the _ regime prepares to take the northern city.

Assad