The Tigray war began on 4 November 2020 when Ethiopian federal forces and Eritrean troops launched an offensive against the Tigray People's Liberation Front (TPLF). It became one of the deadliest conflicts of the 21st century. A study by Ghent University and U.S. government estimates suggest between 300,000 and 500,000 combat deaths; with famine and disease, total deaths may reach 600,000. The UN documented mass atrocities, sexual violence used as a weapon of war, and deliberate obstruction of humanitarian aid. A cessation of hostilities was signed in November 2022.