Now-indicted former congressional IT aide Imran Awan allegedly routed data from numerous House Democrats to a secret server. Police grew suspicious and requested a copy of the server early this year, but they were provided with an elaborate falsified image designed to hide the massive violations. The falsified image is what ultimately triggered their ban from the House network Feb. 2, according to a senior House official with direct knowledge of the investigation.

The secret server was connected to the House Democratic Caucus, an organization chaired by then-Rep. Xavier Becerra. Police informed Becerra that the server was the subject of an investigation and requested a copy of it. Authorities considered the false image they received to be interference in a criminal investigation, the senior official said.

Data was also backed up to Dropbox in huge quantities, the official said. Congressional offices are prohibited from using Dropbox, so an unofficial account was used, meaning Awan could have still had access to the data even though he was banned from the congressional network.