Attack on bus kills 23 Syrian troops - war monitor 

An attack on a military bus in Syria's east killed 23 government troops and wounded more than 10, the Syrian Observatory for Human Rights (SOHR) war monitor said Friday, blaming the Islamic State group that operates sleeper cells in lands it once ruled. 

The attack took place near the town of al-Mayadeen in the vast desert province of Deir Ezzor, which is split in control between Syrian troops, backed by Iran and Russia, and Kurdish-led fighters, backed by the United States. 

The SOHR described it as the deadliest attack so far this year by Islamic State. The group, which seized wide swathes of Syria and neighbouring Iraq from 2013, has gone underground since losing its last territory in eastern Syria in 2019.

Syrian state media carried no immediate reports on the incident and there was no immediate claim of responsibility. 

Attacks by Islamic State sleeper cells in Syria, particularly in the vast desert zones they once controlled, have become bolder and bloodier in recent months, according to SOHR head Rami Abdel Abdelrahman. 

Islamic State named Abu Hafs al-Hashimi al-Quraishi as its new leader this month, for the first time confirming the death of its former head Abu Hussein al-Husseini al-Quraishi, whom Turkey said it had killed in April.