Complex sentence: Sisak special police was assigned to support the Glina Battalion, and indirectly the main offensive force, while the 36th Engineering-Pontoon Battalion was tasked with facilitating the Kupa River crossing by the 102nd Infantry Brigade.
Split into simpler sentences: Sisak special police were assigned to support the Glina Battalion, and indirectly the main offensive force. The 36th Engineering-Pontoon Battalion was tasked with the Kupa River crossing by the 102nd Infantry Brigade.