(TEHRAN, Iran) — Iran and the U.S. conducted a prisoner exchange Saturday that saw a detained Princeton scholar released for an Iranian scientist held by America, marking a rare diplomatic breakthrough between Tehran and Washington after months of tensions. In a trade conducted in Zurich, Switzerland, Iranian officials handed over Chinese-American graduate student Xiyue Wang, detained in Tehran since 2016, for scientist Massoud Soleimani, who had faced a federal trial in Georgia. While the exchange represents a rare win for both countries, it comes as Iran still faces crushing American sanctions and the aftermath of nationwide protests that reportedly saw over 200 people killed.