Col. Riad Al-Asaad says the regime launched the brutal crackdown last week on the town of Rastan to try to capture him and his comrades who battled against the military. The army retook the town after five days of heavy fighting.

Al-Asaad spoke to The Associated Press on Wednesday over the telephone.

He says he defected from the army in July after refusing to heed orders to shoot at protesters.

Syrian military defections have since then increased.

Al-Asaad says the Free Syrian Army how has more than 10,000 defectors and is becoming the most serious challenge to President Bashar Assad’s regime.