More than 140 people were killed in bombings, occurring within hours of one another, in the cities of Homs and Damascus in Syria on Sunday.
Islamic State claimed both attacks, the Amaq news agency, which supports the militant Sunni group, reported.
At least 83 people were killed in four bomb attacks that hit a Shi'ite suburb of Damascus, pro-government media outlets and a monitoring group said, hours after a deadly twin attack hit the city of Homs, killing 59.
Residents said the attack was about a kilometer (0.6 mile) from one of Shi'ite Islam's holiest shrines and did not damage it.
Four blasts hit al-Tin street in Sayeda Zeinab, pro-Damascus al-Ikhbariya said in a newsflash. It said two of the blasts were car bombs and the other two had been detonated by suicide attackers. State TV said the blasts hit near the al-Sadr hospital in Sayeda Zeinab.
Suicide attacks last month claimed by Islamic State in the district killed 60 people.
Hours earlier, a twin bomb attack in the city of Homs killed at least 59 people, according to the Observatory. The car bomb attacks on Sunday in Homs, in which at least 100 were also wounded, were among the deadliest in the city in five years of civil war, a monitoring group said.
Also on Sunday, U.S. Secretary of State John Kerry said he and his Russian counterpart Sergei Lavrov had reached a provisional agreement on terms of a cessation of hostilities in Syria and the sides were closer to a ceasefire than ever before.
But he indicated there were still issues to be resolved and he did not expect any immediate change on the ground.
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