Syrian rebels launched a surprise attack on Saturday and quickly advanced through several provinces in the north and northwest of Syria, including the city of Aleppo, the country’s second largest city.

Insurgents broke through government defense lines in Aleppo on Friday and entered the city’s western neighborhood with little resistance. The insurgents launched their shock offensive in Aleppo and Idlib countryside on Wednesday and wrestled control of dozens of villages and towns along the way,

The Syrian regime has rushed in reinforcements to hold off a rebel advance into the Hama countryside, after the insurgents seized the country’s second city Aleppo in the biggest threat to autocratic ruler Bashar al-Assad in years.

Insurgents have breached the Syrian city of Aleppo, clashing with government forces, according to a Syria war monitor and fighters.

The Syrian military has rushed in reinforcements to push back insurgents from advancing farther into the northern Hama countryside after they seized Aleppo in a surprise offensive.

Syrian and Russian jets are stepping up strikes on opposition forces in northern Syria in retaliation for the sudden offensive that has cost the regime control of the country’s second largest city, Aleppo.

Thousands of Syrian insurgents took over most of Aleppo on Saturday, establishing positions in the country's largest city and controlling its airport before expanding their shock offensive to a nearby province.

Syria and Russia are stepping up their retaliatory strikes on forces in northern Syria after they lost control of the country’s second-largest city.

Syrian rebels drove military vehicles around Aleppo province as clashes with Syrian government forces escalated. Fighting in northwestern Syria over the past three days has claimed the lives of 27 civilians,