Complex sentence: There was an expectation that the Australian Navy would send a destroyer in search of the missing ship but controversially the Navy refused to do so, which led to some unfavourable press reports and representations from citizens arguing that a ship should be sent.
Split into simpler sentences: There was an expectation that the Australian Navy would send a destroyer in search of the missing ship but, controversially, the Navy refused to do so. That decision led to some unfavourable press reports and representations from citizens arguing that a ship should be sent.