Top US intelligence chiefs publicly expressed doubts about the global cybersecurity firm Kaspersky Labs because of its roots in Russia.

Six leading intelligence officials yesterday told a Senate hearing on external threats to the United States of their concerns over the firm’s broad presence, without specifying the particular threat they see.

Asked if he was aware of a security threat tied to Kaspersky software, Federal Bureau of Investigation acting director Andrew McCabe replied, “We are very concerned about it and we are focused on it very closely.”

Defense Intelligence Agency director Lieutenant General Vincent Stewart said his agency is avoiding the company’s products as well. “There is, as well as I know, no Kaspersky software on our networks,” he said, adding that the agency’s private sector contractors are also not using it.

Also indicating their concerns in brief were the heads of the Central Intelligence Agency, the National Security Agency, the National Geospatial Intelligence Agency and the Director of National Intelligence. “I am personally aware and involved as director of the National Security Agency in the Kaspersky Lab issue,” NSA head Mike Rogers said.

Kaspersky was founded in Moscow in 1997 by Eugene Kaspersky, a computer engineer who served in the Russian military. The company quickly expanded to a global presence, with 3,600 employees, 400 million users of its software, and revenue of some $620 million in 2015, according to its website.

Its antivirus programs regularly rank in the top five of such software for personal and business computers.

But US officials have expressed doubts because of its recruitment of some staff with alleged links to Russian defense and intelligence bodies.

US officials are particularly worried about the threat that foreign hackers could penetrate US infrastructure via suspect software and malware.

Kaspersky denied having ties to any government. “The company has never helped, nor will help, any government in the world with its cyberespionage efforts,” it said in a statement on Thursday.

“Kaspersky Lab believes it is completely unacceptable that the company is being unjustly accused without any hard evidence to back up these false allegations.”

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