Complex sentence: Malaysia confrontation (September 1963--May 1965), which stemmed from Indonesia's opposition to the creation of Malaysia, and followed incidents of unrest in Geylang which the Prime Minister's Office claimed to have been instigated by "Indonesian agents and fifth columnists".
Split into simpler sentences: Malaysia confrontation (September 1963--May 1965) stemming from Indonesia's opposition to the creation of Malaysia. This followed incidents of unrest in Geylang which the Prime Minister's Office claimed to have been instigated by "Indonesian agents and fifth columnists".