Rebels and pro-government forces clashed this morning in Yemen, killing 19 people. This is the latest in a series of violent eruptions, which are putting increased strain on a truce between the government and rebels. The violence also indicates that al-Qaida may be growing in strength in Yemen, where in the south of the country there's a separate insurgency involving al-Qaida rebels. The BBC's Jon Leyne describes the violence and the challenges of stabilizing a country with scarce resources. "The bottom line is that the country is in a real mess," says Leyne.