Trump officials got a lesson in the Streisand effect—whereby attempts to suppress information only circulate it further—as their outrage over ICEBlock, a free iPhone app that monitors the activity of Immigration and Customs Enforcement agents, propelled the app to the top of Apple’s App Store on Tuesday.

DHS Secretary Kristi Noem said the Trump administration is exploring prosecuting CNN for reporting on an app that alerts users to nearby ICE agents.

The report from CNN’s Clare Duffy on Monday was on the app ICEBlock, featuring an interview with its developer, Joshua Aaron. He said that he created the app after watching Trump’s immigration crackdown, and compared the arrest of suspected undocumented immigrants to what happened in Nazi Germany.