Chinese and Iranian hackers have attempted to hack the email addresses of Donald Trump and Joe Biden campaigners.
Shane Huntley, a senior security officer at Google, writes on Twitter on Thursday. Trump and Biden are likely to compete in the U.S. presidential election in November.
Huntley writes that their own governments supported the hackers. Details about the hacking attempts have not been made.
It is also unclear what the motives of China and Iran would be. Trump and Biden have not yet responded, as have the Iranian and Chinese authorities.
It is not the first time that U.S. campaign workers have been attacked online.
Last year, Microsoft announced that Iranian hackers were attempting to hack into Trump campaign campaigners’ email boxes. That group of hackers works under the name Charming Kitten.
In the previous 2016 U.S. presidential election, Russia was accused of hacking. Moscow would have wanted to influence the elections at the time.