SYDNEY, Australia — One journalist is being investigated for reporting that several boats filled with asylum seekers recently tried to reach Australia from Sri Lanka. Another reporter had her home raided by the authorities this week after reporting on a government plan to expand surveillance powers.

Then on Wednesday, the Australian federal police showed up at the main public broadcaster with a warrant for notes, story pitches, emails, and even the diaries for entire teams of journalists and senior editors — all in connection with a 2017 article about Australian special forces being investigated over possible war crimes in Afghanistan.

The aggressive approach — which Australia’s prime minister, Scott Morrison, has defended — fits with a global trend. Democracies from the United States to the Philippines are increasingly targeting journalists to ferret out leaks, silence critics and punish information sharing — with President Trump leading the verbal charge by calling journalists “the enemy of the people.”

But even among its peers, Australia stands out. No other developed democracy holds as tight to its secrets, experts say, and the raids are just the latest example of how far the country’s conservative government will go to scare officials and reporters into submission.