The U.S. State Department is calling for the release of prominent human rights activist Nabeel Rajab, who is reportedly facing new charges after he wrote an op-ed for The New York Times earlier this week. In the piece headlined “Letter from a Bahraini Jail,” Rajab says he was being held, in part, for having criticized the U.S.-backed, Saudi-led war in Yemen. He called for the U.S. to stop backing Saudi Arabia, writing that the United States’ “unconditional support for Saudi Arabia and its lifting of the arms ban on Bahrain have direct consequences for the activists struggling for dignity in these countries.” Rajab was rearrested this past June. He’s been imprisoned multiple times in recent years for participating in pro-democracy protests and for criticizing the Bahraini government. On Tuesday, State Department spokesperson Mark Toner called for his release.

Mark Toner: “We’re obviously concerned about Nabeel Rajab’s detention and the charges filed against him, and we call on the government of Bahrain to release him. We have concerns about the state of human rights, in general, in Bahrain, and we’re engaging with the government of Bahrain on all of these issues.”

Bahrain is a close U.S. ally, home to the Navy’s Fifth Fleet.