ISIS has claimed responsibility for multiple attacks in strongholds of the Syrian regime Sunday that killed at least 122 people and scores of others injured, according to Syria's state-run SANA news agency.
The separate car bomb and suicide attacks happened in Homs and southern Damascus, Syrian state media reported, citing local officials and security sources.
The deadliest attacks were on the southern outskirts of Damascus, where three bombers struck in the Sayyidah Zaynab district.
The blasts detonated near the revered "Lady Zeynab" Shia Muslim shrine, SANA reported. At least 83 were killed and 178 others injured there, according to SANA, citing its reporter on the scene and local sources.
Thirty-nine people were killed when two car bomb explosions struck a pro-regime neighborhood in central Homs, SANA reported.
The London-based monitoring group Syrian Observatory for Human Rights gave the death toll as 46, with more than 100 people wounded.
The observatory reported that the Damascus attacks were carried out via a suicide car bomb and by two suicide bombers.
ISIS claimed responsibility for the Sayyidah Zaynab and Homs attacks via the Telegram messaging app.
The U.N. Special Envoy for Syria, Staffan de Mistura, condemned the attack, saying that children were among the victims.