Question: Which operation was this military offensive, which put an end to the conflicts between Lithuanian and Polish units known as Dubingiai massacre, a part of?
Context: The Glinciszki massacre was a mass murder of Polish civilians by the Nazi-subordinated Lithuanian Auxiliary Police Battalion, committed on 20 June 1944 in the village of Glinciszki (now Glitiškės, Vilnius District Municipality, Lithuania) during the occupation of Poland in World War II.  In the massacre, 39 hostages died, including 11 women (one in advanced stage of pregnancy), 11 children (some as young as 3 years old), and 6 elderly men.  They were executed as a collective punishment for the death of four Lithuanian Nazi policemen on the previous evening, during the skirmish with the Polish resistance units of the 5th Brigade of Armia Krajowa commanded by Lieutenant Wiktor Wiącki.  The massacre triggered an act of reprisal by the Polish partisans against Lithuanian civilians in Dubingiai two days later. The Hama offensive (March–April 2017) was a military offensive launched by Syrian rebel groups led by Hay'at Tahrir al-Sham (HTS) north of the city of Hama, as part of the Syrian Civil War.  The offensive began on 21 March 2017, and the rebels aim to recapture areas recaptured by the Syrian Armed Forces in the 2016 Hama offensive, as well as pushing into Hama city.  The offensive was coordinated with rebel forces in Damascus' eastern suburbs, who launched their own operation in March 2017. The Lithuanian–Soviet War or Lithuanian–Bolshevik War (Lithuanian: "karas su bolševikais" ) was fought between newly independent Lithuania and the Russian Soviet Federated Socialist Republic in the aftermath of World War I.  It was part of the larger Soviet westward offensive of 1918–1919.  The offensive followed retreating German troops with intentions to establish Soviet republics in Ukraine, Belarus, Lithuania, Latvia, Estonia, Poland and link up with the German Revolution.  By the end of December 1918 Soviet forces reached Lithuanian borders.  Largely unopposed, they took one town after another and by the end of January 1919 controlled about ⅔ of the Lithuanian territory.  In February the Soviet advance was stopped by Lithuanian and German volunteers, who prevented the Soviets from capturing Kaunas, the temporary capital of Lithuania.  From April 1919 the Lithuanian war went parallel with the Polish–Soviet War.  Poland had territorial claims over Lithuania, especially the Vilnius Region, and these tensions spilled over into the Polish–Lithuanian War.  Historian Norman Davies summarized the situation: "the German army was supporting the Lithuanian nationalists, the Soviets were supporting the Lithuanian communists and the Polish Army was fighting them all."  In mid-May the Lithuanian army, now commanded by General Silvestras Žukauskas, began an offensive against the Soviets in northeastern Lithuania.  By mid-June the Lithuanians reached the Latvian border and cornered the Soviets among lakes and hills near Zarasai, where the Soviets held out until the end of August 1919.  The Soviets and Lithuanians, separated by the Daugava River, maintained their fronts until the Battle of Daugavpils in January 1920.  As early as September 1919 the Soviets offered to negotiate a peace treaty, but talks began only in May 1920.  The Soviet–Lithuanian Peace Treaty was signed on July 12, 1920.  Soviet Russia fully recognized independent Lithuania. The Dubingiai massacre was a mass murder of 20–27 Lithuanian civilians in the town of Dubingiai (Dubinki) on 23 June 1944.  The massacre was carried out by the 5th Brigade of Armia Krajowa (AK), a Polish resistance group, in a reprisal for the Glinciszki (Glitiškės) massacre of 20 June.  The Dubingiai massacre started a wider AK operation in which units beyond the 5th Brigade were involved.  In total, 70–100 Lithuanians were killed by the end of June 1944 in Dubingiai and the neighbouring villages of Joniškis, Inturkė, Bijutiškis, and Giedraičiai.  While Nazi collaborators were ostensibly the prime targets, the victims included the elderly, children, and even infants.  Further conflicts between Lithuanian and Polish units were prevented by the Soviet capture of Vilnius in mid-July. Operation Goranboy was a large-scale military offensive by Azerbaijan in the summer of 1992.  Its aims were to take complete control of the entire territory of Nagorno-Karabakh and put a decisive end to the secessionist Nagorno-Karabakh Republic.  This offensive is regarded as a successful breakthrough by the Azerbaijani Army and marked the peak of Azerbaijani success throughout the entire six-year Nagorno-Karabakh War.  It also marked the beginning of a new, more intense phase of that war.  Over 8,000 Azeri troops and 4 additional battalions, at least 90 tanks and 70 infantry fighting vehicles, as well as Mi-24 attack-helicopters were used in the offensive. The Vilnius Offensive (Russian: Вильнюсская наступательная операция ) occurred as part of the third phase of Operation Bagration, the great summer offensive by the Red Army against the "Wehrmacht" in June and July, 1944.  The Vilnius Offensive lasted from 5 July to 13 July 1944, and ended with a Soviet victory. Karen Marón is an Argentine journalist, war correspondent, producer, international analyst and writer, renowned as one of the TOP 100 most influential war correspondents in the world in covering armed conflicts , with coverage in more than 30 countries since 2000.  As international correspondent specialized in armed conflicts and international politics she has covered conflicts in the Middle East, Latin America, Persian Gulf including the most dangerous places of the world as Iraq, Syria, Lebanon, Colombia, Libya and the Israeli–Palestinian conflict from the Second Intifada up to Israel's military offensive on Gaza Strip. Operation Summer '95 (Bosnian, Croatian: "Operacija Ljeto '95" ) was a joint military offensive of the Croatian Army (HV) and the Croatian Defence Council (HVO) that took place north-west of the Livanjsko field, and around Bosansko Grahovo and Glamoč in western Bosnia and Herzegovina.  The operation was carried out between 25 and 29 July 1995, during the Croatian War of Independence and the Bosnian War.  The attacking force of 8,500 troops commanded by HV's Lieutenant General Ante Gotovina initially encountered strong resistance from the 5,500-strong Army of Republika Srpska (VRS) 2nd Krajina Corps.  The HV/HVO pushed the VRS back, capturing about 1600 km2 of territory and consequently intercepting the KninDrvar roada critical supply route of the self-declared Republic of Serbian Krajina (RSK).  The operation failed to achieve its declared primary goal of drawing VRS units away from the besieged city of Bihać, but it placed the HV in position to capture the RSK's capital Knin in Operation Storm days later. The French Military Mission to Poland was an effort by France to aid the nascent Second Polish Republic after it achieved its independence in November, 1918, at the end of the First World War.  The aim was to provide aid during the Polish-Soviet War (1919–1921), and to create a strong Polish military to serve as a useful ally against Germany.  It was an advisory body consisting of about 400 French officers attached to staffs of Polish units at various levels.  Although the French mission was small numerically, its effect was substantial in improving the organisation and logistics of the Polish army.  It worked in parallel with the smaller British Military Mission to Poland.  It existed from 1918 to 1939. The Manbij offensive, code-named Operation Martyr and Commander Faysal Abu Layla by the SDF, was a 2016 military offensive operation by the Syrian Democratic Forces (SDF) to capture the city of Manbij from the Islamic State of Iraq and the Levant (ISIL), and eventually, the ISIL-held areas through Al-Bab to Herbel, in the area referred to as the "Manbij Pocket" in the northern Aleppo Governorate.  The main goal of the offensive was to cut off ISIL's last supply routes from Turkey, and to prevent ISIL fighters from escaping across the border.  During the first 5 days of the offensive, the US-led coalition conducted over 55 airstrikes in support of the SDF.  After capturing Manbij city on 12 August, the SDF announced that the offensive would continue until the whole countryside around Manbij was captured, though the offensive effectively ended shortly after Turkish-backed forces started Operation Euphrates Shield.
Answer: Operation Bagration