The FBI and CIA have launched a criminal investigation into the public release of documents said to detail CIA hacking tools.
The federal agencies were co-ordinating the inquiry after WikiLeaks published thousands of files.
These carried claims that the CIA had developed ways to listen in on smartphone and smart TV microphones.
The CIA, FBI and White House have declined to comment on the authenticity of the files leaked on March 7.
On March 8, CIA officials – who spoke on the condition of anonymity – told media that the criminal investigation was looking into how the files came into WikiLeaks’ possession.
The inquiry would also try to establish whether the disclosure was a breach from inside or outside the CIA, the officials added.
The CIA has not confirmed whether the documents – said to date between 2013 to 2016 – are real.
Several of the tech companies whose products have been allegedly compromised by the CIA gave their first reactions on March 8.
Apple said it had already addressed some of the vulnerabilities.
“The technology built into today’s iPhone represents the best data security available to consumers, and we’re constantly working to keep it that way,” it said.
Samsung – whose F8000 series of TVs was reportedly compromised – said that “protecting consumers’ privacy and the security of our devices is a top priority at Samsung”.
The leaks also claimed that the CIA had created malware to target PCs running Microsoft’s Windows operating system.
“We are aware of the report and are looking into it,” a spokesman from Microsoft said.
Google has also reacted to claims that the CIA was able to “penetrate, infest and control” Android phones due to its discovery and acquisition of “zero day” bugs – previously unknown flaws in the operating system’s code.
“As we’ve reviewed the documents, we’re confident that security updates and protections in both Chrome and Android already shield users from many of these alleged vulnerabilities,” the company told the news site Recode.
“Our analysis is ongoing and we will implement any further necessary protections. We’ve always made security a top priority and we continue to invest in our defenses.”
The World Wide Web Foundation – which campaigns for internet privacy – said the US government needed to issue a detailed response.