Censor.NET reports citing ВВС.
Activists said both Syrian and Russian warplanes are taking part in the latest offensive, though Russia has not confirmed its involvement. Russia supports the Syrian government, while the U.S. backs the opposition.
UNICEF says fierce strikes on Friday prevented repairs to a damaged pumping station supplying rebel-held districts of the city. In retaliation, UNICEF says, a nearby station pumping water to the rest of Aleppo has been switched off.
Fresh strikes were reported in the city on Saturday, as the Syrian army presses on with its push to retake rebel areas. The latest offensive was launched after the cease-fire collapsed on Monday.
UNICEF spokesman Kieran Dwyer said the lack of running water could be "catastrophic" as residents now had to resort to contaminated water and were at risk from waterborne diseases. He also said water was being used as a weapon of war by all sides.
The Syrian Observatory for Human Rights, a UK-based group monitoring the conflict, said 25 people had been killed in fresh bombardments on Saturday.
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