N'DJAMENA, April 13 (Reuters) - Residents of Chad's capital N'Djamena were woken by the sound of artillery fire early on Thursday as government forces battled to keep rebels bent on overthrowing President Idriss Deby out of the city. A Reuters reporter living in a southern neighbourhood said the noise of heavy weapons could be heard coming from a few kilometres (miles) outside the city. "Everyone is up, wondering what is going to happen," he said. One resident reported seeing a column of smoke.
