Federal investigators have issued Treasury Department subpoenas to prominent streamer Hasan Piker and CodePink cofounder Medea Benjamin as part of an investigation into potential violations of U.S. sanctions against Cuba.

The subpoenas are connected to trips the activists made to Cuba, with investigators examining whether their travel and activities violated existing federal restrictions on American citizens' engagement with the communist-governed island nation.

Piker, a political commentator and Twitch streamer known for his democratic socialist views, participated in what has been described as an aid convoy to Cuba. Benjamin, a longtime anti-war activist and cofounder of the women-led peace organization CodePink, has been involved in similar advocacy efforts regarding Cuba.

The investigation appears to focus on whether the activists' Cuba-related activities ran afoul of the complex web of U.S. economic sanctions that have been in place against Cuba for decades. These sanctions generally prohibit most American citizens from traveling to Cuba for tourism and restrict various forms of economic engagement with Cuban entities.

The Treasury Department's Office of Foreign Assets Control typically handles enforcement of sanctions violations, which can result in both civil and criminal penalties. Neither Piker nor Benjamin has publicly commented on the subpoenas or the ongoing investigation.