Hillary Clinton’s campaign team is using the encrypted application Signal for communicating on sensitive topics, according to a report.

The campaign changed tactics after the Democratic National Committee’s emails were hacked, which came to light this summer. “In the intervening weeks, staffers were told … that if anyone was going to communicate about Donald Trump over e-mail or text message, especially if those missives were even remotely contentious or disparaging, it was imperative that they do so using an application called Signal,” according to a report in Vanity Fair.