Terrorist groups in Syria have violated the nationwide ceasefire on several occasions (23 times) since it was put in place on Monday, according to the Russian military.

Six people died in Aleppo during the attacks while 10 others sustained injuries.

The Syrian government has been abiding by the truce, RT quoted Russian General Staff official Viktor Poznikhir as saying.

"Syrian government forces have completely stopped [their] shelling, except for the areas occupied by ISIL [Islamic State of Iraq and the Levant] and al-Nusra Front [Fatah Al-Sham Front] militants. Unfortunately that can’t be said about the armed forces of the moderate opposition, backed by the United States,” Poznikhir said.

The so-called moderate rebels, supported by the United States have targeted residential areas as well as Syrian Army positions, according to the top Russian official.

Colonel Sergey Kopysin from the Russian Reconciliation Center in Syria said Tuesday that six people were killed on the night before after the shelling of Aleppo by the so-called moderate opposition forces.

Russia and the United States have brokered a ceasefire in Syria. The truce came into effect on Monday at 7pm local time (16:00 GMT).

Then the Syrian Army announced that it will abide by an even longer term of seven days.

The ceasefire is part of a wider peace plan which has been agreed by Russia and the United States last Friday in Geneva.