BOPA (Danish: Borgerlige Partisaner, Civil Partisans) was a group of the Danish resistance movement; it was affiliated with the communists and developed after the occupation of Denmark by Nazi Germany during the Second World War. Operations grew in magnitude as individuals with inside knowledge of possible targets joined the group. Young apprentices from large factories proved especially useful in identifying targets that were supplying the German military. The cells attacked factories such as Burmeister & Wain and in 1943, Riffelsyndikatet (again) and Global in 1944, and Always in 1945.