Evidence is growing that Turkey’s president is ailing—and that could be bad news for the country’s politics.

Multiple Nigerian media outlets reported last week that Boko Haram leader Abubakar Shekau has died or been mortally wounded in a confrontation with fighters from the Islamic State in West Africa (ISWA), a group that separated from Shekau’s Boko Haram in 2016. The Nigerian government has not confirmed the reports and is investigating. The caution is well-placed: Shekau has been reported dead at least four times since he became the leader of Boko Haram in 2009 following the police killing of founder Mohammed Yusuf.