A French scientist on his way to a conference in the United States was allegedly denied entry by Customs and Border Patrol over messages found on his phone that criticized President Trump’s science cuts.

The French newspaper Le Monde reports that on March 9, a space researcher was randomly selected upon arrival in Houston for a search, and CBP found messages criticizing the Trump administration’s treatment of scientists, which, according to the agency, “conveyed hatred of Trump & could be qualified as terrorism.”

The researcher’s phone and computer were allegedly confiscated, and he was sent back to Europe the next day. The news prompted the attention of the French government, which expressed alarm.