In a corridor of land in north east Sri Lanka, some 200,000 civilians are trapped between government forces and Tamil rebels. By one estimate, 40 people are being killed every day. A 30-year civil war is entering a decisive and atrocious phase. Intervention is essential to avert a humanitarian catastrophe. A recent military surge has seen the Liberation Tigers of Tamil Eelam effectively besieged. Fired by the prospect of eradicating the insurgency once and for all, the army is waging a war with no regard for civilian lives. They are also trying to operate without witnesses, refusing access to foreign observers and journalists. Last week, Sri Lankan authorities rejected the appointment of a British government envoy to the region as interference in their internal affairs. That line is easily deployed against the former colonial power; it would be less effective against the combined voice of the UN. The Tigers, meanwhile, also have a brutal reputation, using civilians as human shields and recruiting by coercion. But the government's latest response is sinister - setting up internment camps to "rehabilitate" Tamils caught up in the conflict. Neither side can be trusted to guarantee the safety of civilians. The Security Council must demand a ceasefire so that refugees can be evacuated. The secretary general should mandate a humanitarian mission to investigate the internment camps. The Sri Lankan government must not be allowed the secrecy it craves to conduct a war against its own people. | 
