The Trump Justice Department secretly seized the phone records of three Washington Post reporters who covered the federal investigation into ties between Russia and Donald Trump’s 2016 presidential campaign, the newspaper said Friday. They also tried to obtain the email records for the three reporters: Ellen Nakashima, Greg Miller, and Adam Entous, who now works at The New Yorker. Federal investigators obtained the records for their work, home, and cellphone numbers from April 15 to July 31, 2017. The three reporters received letters informing them of the seizure that did not specify what the seizure was about. But the three reporters wrote a piece published July 21, 2017 about classified intelligence intercepts that indicated Russia’s ambassador to the United States had discussed the Trump campaign with Sen. Jeff Sessions.

The documents that were seized are known as toll records and include the numbers of all the calls made to and from the phone numbers over the time period and how long each call lasted. The three reporters were also told that prosecutors tried to get a court order for “non content communication records” for their work email accounts but they never got those records. Though it wasn’t clear what specifically provoked the searches through the records, Washington Post reporters broke major stories about Trump allies like Jeff Sessions meeting with the Russian ambassador to discuss the Trump campaign, as well as the Obama administration’s efforts to investigate Russian interference. The Obama administration, for its part used the 1917 Espionage Act more often than all other administrations combined to prosecute leakers.