Explosion rocks Syria's Aleppo as residents return

This photo released by the Syrian official news agency SANA, shows Syrian army soldiers flash the victory sign near their tank in the Sukkari neighborhood, east Aleppo, Syria, Friday, Dec 23, 2016. Syrian rebels outside Aleppo on Friday shelled a neighborhood in the northern city, killing three people in the first bombardment since government forces took control of the whole city after opposition fighters in the eastern parts withdrew, state TV reported. (SANA via AP) (The Associated Press)

This photo released by the Syrian official news agency SANA shows Syrian army soldiers marching through the streets in the Ansari neighborhood, east Aleppo, Syria, Friday, Dec 23, 2016. Syrian rebels outside Aleppo on Friday shelled a neighborhood in the northern city, killing three people in the first bombardment since government forces took control of the whole city after opposition fighters in the eastern parts withdrew, state TV reported. (SANA via AP) (The Associated Press)

This photo released by the Syrian official news agency SANA, shows damaged buildings and cars in the Ansari neighborhood, east Aleppo, Syria, Friday, Dec 23, 2016. Syrian rebels outside Aleppo on Friday shelled a neighborhood in the northern city, killing three people in the first bombardment since government forces took control of the whole city after opposition fighters in the eastern parts withdrew, state TV reported. (SANA via AP) (The Associated Press)

Syrian state TV says an explosion rocked eastern Aleppo as some residents were returning to their homes after the government assumed full control of the city earlier this week.

It says the explosion on Saturday was caused by a device left inside a school by Syrian rebels, who withdrew from their last remaining enclave under a cease-fire deal after more than four years of fighting.

A correspondent for Lebanon's Hezbollah-run Al-Manar TV was reporting live from the area when the blast sounded in the background, sending a huge cloud of dust into the air. The correspondent later said that at least three people were killed.

The rebel pullout from Aleppo, which was completed on Thursday, marks President Bashar Assad's greatest victory since the conflict began in 2011.