(Bloomberg) -- Two US senators on Monday expressed their concern to Meta Platforms Inc. Chief Executive Officer Mark Zuckerberg over the risk of developers in China and Russia having access to user data.

Mark Warner, a Virginia Democrat and chairman of the Senate Intelligence Committee, and Marco Rubio of Florida, the panel’s top Republican, in a letter cited documents from a court case that said Meta’s Facebook unit knew in 2018 that “hundreds of thousands of developers in countries Facebook characterized as ‘high-risk,’ including the People’s Republic of China (PRC), had access to significant amounts of sensitive user data.”

The senators said their staff had held meetings with company executives to determine who, exactly, could get at the data, and what Facebook planned to about it, particularly with regards to protecting users’ information. 

“Given those discussions,” Warner and Rubio wrote, “we were startled to learn recently, as a result of this ongoing litigation and discovery, that Facebook had concluded that a much wider range of foreign-based developers, in addition to the PRC-based device-makers, also had access to this data.”

That included 42,000 developers in Russia, and developers in North Korea and Iran, the senators said. 

In a statement, the company said the documents “are an artifact from a different product at a different time. Many years ago, we made substantive changes to our platform, shutting down developers’ access to key types of data on Facebook while reviewing and approving all apps that request access to sensitive information.” Meta said the numbers and predicted location of the developers called out in the case were from before 2014. 

The senators asked Zuckerberg a series of questions, including whether the company was able to identify the developers, communications with them, and to supply what kinds information that developers in China and Russia might have been able to glean.

--With assistance from Michael Bruning and Emily Birnbaum.

(Updates with time period of allegations in sixth paragraph.)

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