According to a new paper authored by two Google security engineers, 21 out of the world’s top 25 news organizations have been successfully hacked by state-sponsored actors.

Reuters reported on the duo's findings, which were presented on Friday at the Black Hat Asia security conference in Singapore.

Among targets of hacking attacks, journalists were “massively over-represented,” Shane Huntley, one of the paper's authors, told the news wire. Google has been monitoring such attacks, which are often sponsored by foreign governments that seek sensitive information held by journalistic enterprises, in many cases related to secretive corporate and governmental operations.

Huntley added, “If you’re a journalist or a journalistic organization, we will see state sponsored targeting and we see it happening regardless of region. We see it from all over the world both from where the targets are and where the targets are from.”

The researchers pointed to the recent breaches of several news organizations including Forbes, The Financial Times, and The New York Times by the Syrian Electronic Army, a group of hackers who regularly pledge support for Syrian President Bashar al-Assad. The group has also successfully hacked into the Associated Press Twitter account.

But pro-Syrian hackers aren’t the only ones to blame. Huntley also told Reuters that Chinese hackers recently gained access to a major Western news organization's internal servers. One method used by such Chinese hackers includes e-mailing fake company questionnaires to members of the organizations’ staff. The e-mails carry malware or instruct users to give up their login credentials on a fake website. (If the US government used such tactics to impersonate websites, as was reported by The Intercept, it could possibly be held liable for trademark infringement.)

It wasn't clear how many of the attacks covered in the research were carried out by the Syrian Electronic Army, which typically publicizes its exploits in an attempt to embarrass its western journalists in the name of Syria's current government. By contrast, recent hacking campaigns against The New York Times and The Washington Post are believed to be carried out by hackers sponsored by the Chinese government. Their objective is to covertly dig up confidential sources and other highly sensitive information. Whatever the case, the attacks do not appear to be limited to large news organizations, as small organizations and citizen-journalists have been targeted as well.

“This is the tip of the iceberg,” Marquis-Boire, the paper's other author, told Reuters.

Story updated to add details in the second-to-last paragraph.