After graduating from the Tbilisi military infantry school in 1942, he was dispatched to the Soviet-German front line, where he commanded a mortar platoon during the Battle of Stalingrad.

In the early 1944, along with two other Azerbaijani POWs, Javad Hakimli and Asad Gurbanov,[2] Huseynzade managed to escape and join the Yugoslav-Italian partisans guerrilla corps.

[3] During the same year, he became a commander of the special reconnaissance diversionary unit of the 9th Corps' Staff of the People's Liberation Army of Yugoslavia, where he got his battlename Mikhailo.

[4] On 2 April 1944, Huseynzade with another Azerbaijani guerrilla, Mirdamat Seidov, installed a delayed-action mine in the Villa Opicina cinema near Trieste.

At the end of April 1944, Huseynzade, Hans Fritz and Ali Tagiyev blew up a bridge near the Postojna railway station, which led to a 24-car train crash.