The Sri Lankan governement rejects allegations of misleading the UN amid fresh violence.
There was no comment from the military. Security forces had been accusing the separatists of firing artillery and mortar bombs towards army camps in the district in recent weeks.
The LTTE and the Sri Lankan government have escalated fighting in the past year in tit-for-tat battles that have claimed thousands of lives despite a 2002 ceasefire agreement.
The bitter ethnic conflict has claimed at least 60,000 lives since it began in 1972.