The leak of sensitive classified US documents was “concerning” but the contents were not of “great consequence”, President Joe Biden said on Thursday,
“I’m concerned that it happened, but there’s nothing contemporaneous that I’m aware of that is of great consequence,” Mr Biden said while in Ireland.
He added there was a “full-blown” investigation taking place involving the Justice Department and intelligence community. “We're getting close,” he said. “But I don't have an answer.”
The leak includes apparent US intelligence assessments of allies that could potentially strain ties.
It is not known how many documents were leaked and estimates have ranged from 50 to several hundred.
Documents may have been altered or used as part of a misinformation campaign, US officials said.
“They were somewhere in the web, and where exactly, and who had access at that point, we don’t know. We simply don’t know,” Defence Secretary Lloyd Austin said on Tuesday.
“We will continue to investigate and turn over every rock until we find the source of this and the extent of it.”
One line of inquiry for the source of the leak appears to be Discord, a social media platform popular with people playing online games.
The Discord site hosts real-time voice, video and text chats for groups and describes itself as a place “where you can belong to a school club, a gaming group or a worldwide art community”.
On Thursday, press secretary Karine Jean-Pierre said the White House urged social media companies to “avoid facilitating the circulation of material detrimental to public safety and national security”.
“We do believe that social media companies have a responsibility to their users and the country to manage the private sector infrastructure that they create and then operate,” she said.