Shelling in the town of Herak, south of Damascus, killed six children on Tuesday, a human rights watchdog said, taking the death toll nationwide to 33 as helicopters strafed second city Aleppo. "At least seven civilians, including six children, were killed by regime forces shelling of the besieged town of Herak," the Syrian Observatory for Human Rights said. A video the Britain-based watchdog distributed showed the bodies of dead children, including a young girl in a pink and white dress, lying on a blood-smeared floor, the faces of some of them covered in blood. "Herak has been under shelling for 10 days," an unidentified man says in the amateur video. "The world is watching. Where are the Arabs and Muslims when these children are killed during Ramadan?" he pleaded, referring to the Muslim holy month which began last week. "Where is Islam? You see these children in the blossom of their youth? "Bashar, I hope your children will suffer the same fate," he screamed, addressing President Bashar al-Assad. By early afternoon, the Observatory put the nationwide death toll at 33, including at least seven people killed when regime forces put down a prison mutiny in second city Aleppo. The opposition Syrian National Council gave a higher toll, saying eight people were killed in the crushing of the mutiny, which followed a similar rebellion last week at the main prison in Syria's third-largest city Homs. Fighting continued to rage in Aleppo, with the Observatory reporting "clashes between rebels and regular troops in the Sukari neighbourhood and on the outskirts of Salaheddin." A spokesman for the rebel Military Council on Monday told AFP that opposition fighters had "liberated" multiple neighbourhoods of the the city, including Salaheddin, as the army continued to bombard the districts. The Observatory said helicopter gunships were firing on the Qadi Askar, Bab Al-Hadid, Al-Katergi and Karam Al-Jabal districts of the city. The Al-Watan newspaper, close to the government, reported that shopping malls in Aleppo, Syria's commercial capital, had been forced to close because of "regrettable events" in certain areas. In Damascus, where the army has been battling to retake control of districts held by rebel forces, the Observatory reported heavy fighting in the districts of Al-Hajar Al-Aswad, where tanks were being used, and Qadam. "The districts of Mazzeh (west), Barzeh (northeast) and Midan (south) are under the total military control of the army, but there are daily arrests," Observatory director Rami Abdel Rahman said. Elsewhere in the country, the Observatory reported that troops were pounding the rebel district of Rastan in Homs province as well as the Kurdish mountains in the northeastern province of Latakia. The watchdog said the army was firing "five to seven shells a minute" in its "heaviest bombardment since the beginning of military operations in the region." And in the central province of Hama, shelling of the village of Latamneh killed six people, including a child, the Observatory said. On Monday, violence across the country killed 116 people -- 64 civilians, 17 rebel fighters and 35 soldiers, according to the watchdog's figures.