Colombo- UN Under-Secretary-General for Humanitarian Affairs John Holmes is due in Sri Lanka for a two-day visit to discuss the plight of civilians in the northern part of the country, where fighting between government troops and Tamil rebels has forced thousands to flee their homes, officials said Wednesday.

Holmes, who arrives on Thursday, will meet Sri Lanka's President Mahinda Rajapaksa and Foreign Minister Rohitha Bogollagama, among others, Bogollagama told reporters.

The visit of Holmes comes a week after the government rejected a visit by British Special Envoy Des Browne, a former defence secretary, who was also due to discuss the humanitarian issues with Sri Lankan leaders.

Holmes' visit comes as the plight of the civilians in the combat area is getting worse and the fighting intensifying.

Military spokesman Brigadier Udaya Nanayakkara confirmed that government troops were heading towards the rebel-held areas in Mullaitivu, 390 kilometres north-east of the capital, from at least four directions.

The government had earlier declared a "safety zone," a stretch of 12 kilometres along the coastline of Mullaitivu.

But the pro-Tamil rebel website Tamilnet Wednesday claimed that the army had carried out artillery attacks into the safety zone killing at least 108 civilians and injuring 200 others. The military has denied firing into the safety zone.

Foreign Minister Bogollagama said that the rebels were giving exaggerated figures of casualties in order to mislead the international community.

The International Committee of the Red Cross (ICRC) has been evacuating injured and ill persons from the coastal areas of Mullaitivu during the past two weeks. More than 1,500 critically injured and ill persons and their family members have been evacuated by sea.

On Wednesday the Sri Lankan government dispatched food and medical supplies to the civilians in the north by sea. This was the first consignment to reach the civilians in two weeks, after Colombo suspended food supplies to the area by road, due to the lack of safety for its convoys.

Reports from the area said that civilians were facing shortages of food and medical supplies during the past few days.

The government has called on the Tamil rebels to allow civilians to leave the area, but the rebels have not responded so far.

Since January, some 35,840 civilians have left the rebel controlled areas and entered the government controlled areas where they are looked after in welfare centres.

Government troops have been fighting their way into rebel-held areas in a series of operations launched since August 2006 in the northern and eastern parts of the country.

All rebel-held areas, except for a 100-square-kilometer territory, have already been captured, according to the military. (dpa)