Definition: In this task, you are given a question and a context passage. You have to answer the question based on the given passage.
Input: Why did broz return to omsk?, Context: After 13 months at the hospital, Broz was sent to a work camp in the Ural Mountains where prisoners selected him for their camp leader. In February 1917, revolting workers broke into the prison and freed the prisoners. Broz subsequently joined a Bolshevik group. In April 1917, he was arrested again but managed to escape and participate in the July Days demonstrations in Petrograd (St. Petersburg) on 16–17 July 1917. On his way to Finland, Broz was caught and imprisoned in the Peter and Paul Fortress for three weeks. He was again sent to Kungur, but escaped from the train. He hid with a Russian family in Omsk, Siberia where he met his future wife Pelagija Belousova. After the October Revolution, he joined a Red Guard unit in Omsk. Following a White counteroffensive, he fled to Kirgiziya and subsequently returned to Omsk, where he married Belousova. In the spring of 1918, he joined the Yugoslav section of the Russian Communist Party. By June of the same year, Broz left Omsk to find work and support his family, and was employed as a mechanic near Omsk for a year.
Output:
a White counteroffensive