An explosive-laden vehicle went off Wednesday in the west of northern Syria\'s Idlib province, causing a number of casualties, the state-run SANA news agency reported.The blast took place between the western towns of Failoun and Bakfalloun, SANA said.Meanwhile, the Britain-based Syrian Observatory for Human Rights said the blast was near an army checkpoint close to the military public housing area in Idlib.Blasts and mortar attacks have become increasingly common in Syria after two years of deadly conflict that has been recently spiced with al-Qaida flavor after the radical group, al-Nusra Front, pledged allegiance to al-Qaida leader Ayman al-Zawahiri.