The below is attributable to Spokesperson Matthew Miller:
Secretary of State Antony J. Blinken spoke today with Serbian President Aleksandar Vucic to urge the de-escalation of tensions with Kosovo. The Secretary welcomed the news of the release of the three Kosovo police officers. The Secretary also reiterated those responsible for attacks on Kosovo Force (KFOR), the NATO-led international peacekeeping force in Kosovo, should be held accountable, emphasized continued U.S. support for the EU’s three-point plan, and urged Serbia to immediately take steps to implement its commitments under the normalization agreement.
Source: U.S Department of State, Bureau of European and Eurasian Affairs