BEIRUT (Reuters) - Russian air strikes killed 21 people in a village on the eastern side of the Euphrates River in east Syria, the Syrian Observatory for Human Rights said on Wednesday. The strikes in Deir al-Zor province were to support the Kurdish-led U.S.-backed Syrian Democratic Forces (SDF) fighting Islamic State, which had attempted to launch an attack on the town earlier this week, the war monitor said. Russia has been carrying out air strikes in the province mainly in support of the Syrian army which, alongside allied Shi ite militias, has been waging its own assault against Islamic State on the western side of the Euphrates. The separate assaults have advanced along opposite sides of the river, which bisects oil-rich Deir al-Zor, mostly staying out of each other s way. The U.S.-led coalition and the Russian military have held deconfliction meetings to prevent clashes between them, though the two offensives have sometimes come into conflict. The Observatory also reported on Wednesday that the Syrian army and its allied forces had  finished the presence of Islamic State  on the western bank of the river. On Sunday, the Syrian Kurdish YPG militia, which spearheads the SDF, announced it had fully captured Deir al-Zor s eastern countryside from Islamic State with the help of both the U.S.-led coalition and Russia. 