FROM wikipedia

The Hungarian Revolution of 1956 caused a split in the DPRK university student population. Some asked to be repatriated,however roughly 200 students joined in the revolution; their war experience proved to be of aid to the Hungarian students, many of whom lacked military training and could not operate the weapons and equipment they captured.In the aftermath of the revolution, Soviet forces and Hungarian police gathered up the North Korean students—easily distinguished from locals by their appearance—and deported them back to the DPRK, with a handful escaping to Austria and Yugoslavia.In January 1957, North Korean newspapers announced the return by train of 775 students from Hungary, due to the "hard situation" there. Some of the students who returned to Kim Il-sung University were reported for sharing news about how the Hungarian people hated their pro-Soviet regime.? The DPRK did not send any more students to Hungary.