The corporate parent of The Wall Street Journal and The New York Post disclosed on Friday that it was hacked, likely by Chinese interests, and that sensitive documents and journalists’ emails have been stolen.

The cyberattack on News Corp occurred on January 20th, the company revealed in a securities filing, and impacted News Corp headquarters, The Journal, The Post, and several of the entity’s U.K. publications.

The Journal reports:

News Corp said it notified law enforcement and hired cybersecurity firm Mandiant Inc. to support an investigation.

“Mandiant assesses that those behind this activity have a China nexus, and we believe they are likely involved in espionage activities to collect intelligence to benefit China’s interests,” said David Wong, vice president of incident response at Mandiant.

The outlet adds:

Law-enforcement officials and cybersecurity experts say that journalists are often high-priority targets for hackers seeking to gain intelligence on behalf of foreign governments, because they speak to sources who might have valuable or sensitive information. Powerful surveillance tools have been used against journalists and human-rights activists.

U.S. authorities have accused China-based hackers for years of targeting a range of American businesses and government institutions. FBI Director Christopher Wray said this week that Beijing is running a “massive, sophisticated hacking program that is bigger than those of every other major nation combined.” The FBI has more than 2,000 active investigations related to allegations of Chinese-government-directed theft of U.S. information or technology, Mr. Wray said.

Reuters provides more context:

Chinese hackers have repeatedly been blamed for hacks of journalists both in the United States and elsewhere.

In 2013, for example, The New York Times reported a breach which it said had affected 53 personal computers belonging to its employees.

The paper said that the timing of the intrusions corresponded with its investigation into the wealth accumulated by relatives of Wen Jiabao, China’s then-prime minister.

The Times said Chinese hackers had also broken into the computers of Bloomberg employees in 2012, after the news agency published a story about the relatives of China’s now-leader, Xi Jinping.