It said the "terrorist explosions" took place in Jibrin - north-east of Hama city - and al-Humeiri.
The attack comes days after scores of people were killed and injured in explosions in government-controlled parts of the central city of Homs.
An agreement was reached on Friday for rebels in Homs to withdraw.
The Syrian Observatory for Human Rights, a UK-based activist group, said that about 1,000 fighters were expected to pull out from rebel-held areas of the besieged city under the terms of a ceasefire.
Rebel fighters have long held onto districts in and around the Old City of Homs. The city has seen some of the worst fighting in the three years of the Syrian conflict.
The Observatory said that under the terms of the deal, rebels will withdraw to the north of Homs province, while the army will take control of areas of the Old City which they have vacated.
"The withdrawal has not begun yet and under the agreement those leaving will be able to keep their weapons," Homs activist Thaer al-Khalidiyeh told the AFP news agency.
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