Syrian troops have bombed and strafed rebels in the key city of Aleppo for days now in preparation for a major assault—and that assault is under way, report al-Jazeera and the BBC. Ground troops and tanks that had been massing on the city's outskirts poured in today, according to the watchdog group the Syrian Observatory for Human Rights (SOHR). The uprising's "fiercest" clashes have claimed at least 29 lives while crowds seek refuge in basements, says SOHR.
Meanwhile, thousands of people are fleeing and "being terrorized by helicopter gunships flying at low altitude," according to an activist. The AP says Aleppo will be "one of the most important battles of the 17-month-old uprising," and Reuters agrees: "The battle for the city of 2.5 million people is seen as a crucial test for a government that has committed major military resources to retaining control of its two main power centers, Aleppo and Damascus, in the face of a growing insurgency." (More Syria stories.)