Complex sentence: Prisoners were usually extremely valuable as they might reveal important intelligence to Special Branch or Selous Scouts, and captured guerrillas frequently turned to work for the Rhodesian Security Forces, sometimes, from 1978, as Security Force Auxiliaries.
Split into simpler sentences: Prisoners were usually extremely valuable as they might reveal important intelligence to Special Branch or Selous Scouts. Captured guerrillas were frequently turned to work for the Rhodesian Security Forces, sometimes, from 1978, as Security Force Auxiliaries.