Professor Stanford J. Shaw gives the following information ragarding the events in Eastern Anatolia in 1914-1915:
"With the Russian invasion of eastern Anatolia in 1914 at the beginning of World War I, the degree of Armenian collaboration with the Ottoman's enemy increased drastically. Ottoman supply lines were cut by guerilla attacks, Armenian revolutionaries armed Armenian civil populations, who in turn massacred the Muslim population of the province of Van in anticipation of expected arrival of the invading Russian armies." (cf. History of the Ottoman Empire and Modern Turkey, Volume II: Reform, Revolution & Republic: The Rise of Modern Turkey, 1808-1975.)
As the Russian forces advanced into Ottoman territory in eastern Anatolia, they were led by advanced units composed of Ottoman and Russian Armenian genocide squads, who were joined by the Armenians who deserted the Ottoman armies and went over to the Russians. Within a few months after the war began, these Armenian genocide squads, operating in close coordination with the Russians, were savagely attacking Turkish and Kurdish cities, towns and villages in the East, massacring their inhabitants without mercy, while at the same time working to sabotage the Ottoman army's war effort by destroying roads and bridges, raiding caravans, and doing whatever else they could to exterminate the entire Muslim population of the Eastern Anatolia and to ease the Russian occupation.
Nor did these Armenian atrocities affect only Turks and other Muslims. The Armenian genocide squads had never been happy with the failure of the Jews to support their genocide programs. As a result in Hakkari and vicinity they slaughtered thousands of Jews.
 Schemsi, Kara, "Turcs et Armeniens devant l'Histoire," Geneva, Imprimerie Nationale, 1919, p. 41 and p. 63.
Basically the aim of these atrocities was to leave only Armenians in the territories being claimed for the new Armenian state; all others therefore were massacred or forced to flee for their lives so as to secure the desired Armenian majority of the population in preparation for the peace settlement.
Extracts from a letter dated December 11, 1983, published in the San Francisco Chronicle, as an answer to a letter that had been published in the same journal under the signature of one B. Amarian:
"We have first hand information and evidence of Armenian atrocities against our people (Jews). Members of our family witnessed the murder of 148 members of our family near Erzurum, Turkey, by Armenian neighbors, bent on destroying anything and anybody remotely Jewish and/or Muslim. Armenians should look to their own history and see the havoc they and their ancestors perpetrated upon their neighbors. Armenians were in league with Hitler in the last war, on his premise to grant themselves government if, in return, the Armenians would help exterminate Jews. Armenians were also hearty proponents of the anti-Semitic acts in league with the Russian Communists." (Signed Elihu Ben Levi, Vacaville, California; also quoted in the sworn statement of Albert J. Amateau given at http://www.sephardicstudies.org/aa3.html.)
A passage from the sworn statement of 20th Century Sephardic Advocate Rabbi Albert J. Amateau (Oct. 11, 1989):
"Fifty thousand Armenians, residents of villages in and around Erzurum in Turkey surreptiously ascended a mountain called Mussa Dagh (dagh is Turkish for mountain) with arms, ammunition, victuals and water, sufficient to withstand a siege of many days. Before ascending that mountain, they had captured hundreds of Muslim Turks and Jews, their fellow citizens and neighbors, with whom they were supposedly on good terms. They murdered them all in cold blood, for no other reason than they were Muslims and Jews." (http://www.sephardicstudies.org/aa3.html)
Professor Justin McCarthy writes:
"By the end of World War I, the Jewish presence in southeastern Anatolia which had existed since antiquity, was over."