The intense battles are raging near the villages of Jbain and Tal Mileh in the northern countryside of Hama province, said the Syrian Observatory for Human Rights.
The Britain-based watchdog group said the Syrian forces are trying to capture the areas under the air and ground shelling cover.
The Observatory said that as many as 147 Syrian soldiers have been killed over the past 72 hours of battles in that region.
It is worth noting that the province of Idlib and the countryside of Hama, as well as the countryside of Latakia and Aleppo countryside areas, are included in a de-escalation zones' deal.
The de-escalation zones' deal was reached between Russia and Turkey in September last year.
Under the deal, the ultra-radical groups should evacuate their areas and hand over their heavy weapons.
However, the al-Qaida-linked militant groups expanded and captured the entire Idlib area and engaged in battles with the Syrian Army and these battles evolved into a full showdown that has started in late April.
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