A former CIA officer who was arrested last week under the suspicion of spying for China is also suspected of compromising American spies in Russia, NBC News reported Friday, citing sources familiar with the matter.

NBC News, citing multiple former and current government officials, said a FBI-CIA task force probing the case concluded that the Chinese government used information it gained about American operations to arrest and execute at least 20 CIA informants.

Authorities believe China shared the information with Russia, which used it to expose and possibly kill U.S. spies, said NBC News, which cited current and former officials who declined to be named.

Read the full NBC News exclusive here.