Hundreds of Turkish riot police used tear gas and forced their way into the Ankara headquarters of the main opposition Republican People’s Party (CHP) on Sunday after a court removed the party’s leadership, Agence France-Presse journalists witnessed. Party members had blocked the entrances of the building, defying a court order issued Thursday as part of an investigation into the CHP. Police moved in to remove party leader Özgür Özel after supporters of former chairman Kemal Kılıçdaroğlu tried to enter the headquarters. Human Rights Watch on Saturday warned that President Recep Tayyip Erdoğan’s government was undermining Turkish democracy through “abusive tactics”...