Several Indonesian media outlets critical of the government's coronavirus response have been hit by a series of computer hacking attacks that the International Federation of Journalists (IFJ) on Tuesday slammed as a threat to press freedom.
At least four organisations have been targeted in an "unprecedented" series of digital attacks recently, which could be aimed at "restricting critical reporting and suppressing media freedom", the group said in a statement.
"IFJ is gravely concerned by these hacking incidents and call on authorities to conduct a thorough investigation," it said.
"These online attacks impede press freedom by creating a climate of fear that could lead to self-censorship."
On Friday, the website of major media outlet Tempo was replaced with a black screen with the word "hoax" in bold red font, while several articles critical of the Indonesian intelligence agency's role in the epidemic response were removed from outlet Tirto's website.
It was not clear who was behind the attacks and neither the police nor the national intelligence agency replied to requests for comment.
Epidemiologist Pandu Riono had his Twitter account hacked after criticising a government-university research collaboration that he said fell below international standards.
The Indonesian embassy in Canberra last week criticised an Australian media report that quoted Riono as saying that the world's fourth most populous nation may already have one million virus cases -- over six times the official figure.
Indonesia had reported over 150,000 COVID-19 cases and 6,759 deaths, but with some of the world's lowest testing rates the true scale is widely believed to be much greater.
The Southeast Asian archipelago of nearly 270 million is among the worst hit in Asia by the epidemic and the government has been sharply criticised for its response.
Dozens of frontline doctors have succumbed to the deadly respiratory disease, while health officials have warned that hundreds of children may have also died from it.