As the Sri Lankan government confronts the Liberation Tigers of Tamil Eelam (LTTE), between 15,000 and 50,000 civilians are estimated to be trapped in the conflict zone - a four square kilometre pocket of land in the northeast.br br Some civilians are now in about 40 overcrowded camps after fleeing LTTE-held areas. Thousands more have fled to the frontline coastal village of Puttumattalan, which until earlier this week, was in the so-called "no fire zone".br br Al Jazeera's David Chater reports.