ALEPPO, Syria, Feb. 28 (UPI) -- While fighting has quieted significantly since a Syrian cease-fire took effect Saturday, a rights group monitoring the situation reported war planes carried out several airstrikes Sunday in the Aleppo region, the southern countryside of Hama and near Raqqa, the de-facto capital of the Islamic State.
It is not clear who conducted the airstrikes but rights activists said Russian planes and rebel groups attacked several sites in northern Syria, BBC News reported.
The Syria Observatory of Human Rights reported 183 dead, among them, two civilians, 24 rebels and 24 non-Syrian Islamic fighters.
Russian officials said nine breaches of the U.S.-Russian planned truce have already been identified in the second day of what was to be a cease-fire, but the first major cessation in the five-year war has mostly held.
Terrorist groups like Islamic State and al-Nusra Front are part of the agreement, called a "cessation of hostilities" between a handful of rebel groups and the Syrian Regime.
The cease-fire was negotiated to allow humanitarian aide to reach beseiged communities in Syria.
The United States and Russia are monitoring the ceasefire from separate command posts and are responsible for deciding whether some attacks against the IS, also known was ISIS, ISIL and Daesh, or the al-Nusra Front, excluded from the deal, are permissible.
More than 2,500 have been killed in the fight against Syrian President Bashar al-Assad.