Turkey’s state-run news agency says authorities have unearthed four more skulls at a suspected mass grave in the country’s Kurdish-dominated southeast, bringing the total of the grim discovery to 23 skulls. The Anadolu Agency, citing the prosecutor’s office, said the three skulls were found Wednesday at the site of a former military unit and prison in the city of Diyarbakir. It is not clear when the victims were buried. Authorities overseeing the excavation over the last two weeks were not available for comment. Separately, authorities investigating alleged extrajudicial killings by Turkish security forces in the 1990s last week exhumed the bodies of three Kurds and apparent human bones at an operating Turkish military outpost in the southeastern province of Sirnak.