SNIP Officials did not disclose the informant’s identity or new location, both closely held secrets. The person’s life remains in danger, current and former officials said, pointing to Moscow’s attempts last year to assassinate Sergei V. Skripal, a former Russian intelligence official who moved to Britain as part of a high-profile spy exchange in 2010. The Moscow informant was instrumental to the C.I.A.’s most explosive conclusion about Russia’s interference campaign: that President Vladimir V. Putin ordered and orchestrated it himself. As the American government’s best insight into the thinking of and orders from Mr. Putin, the source was also key...
