The UN refugee agency, UNHCR, said on Friday it has begun emergency airlifts of humanitarian supplies to 20,000 desperate internally displaced Somalis in the war-scarred nation.

In a statement, the UNHCR said the airlift flights started airlifts on Thursday carrying more than 28 tons of much-needed relief supplies to Baidoa, 230 km northwest of Mogadishu.

"Trucks are now carrying the aid items southwards to Afgooye, where there are at least 18,000 displaced Somalis who fled recent fighting in the Somali capital," the statement said. Afgooye is 30 km west of Mogadishu.

"The airlifted supplies consist of 9,000 blankets, 1,800 plastic sheets, 3,600 jerry cans and 1,800 kitchen sets which will be distributed to displaced families mainly in Afgooye and Marka," it said.

The UN agency said thousands of displaced Somalis have spent nearly two weeks without proper food, water or shelter, adding that families with no relatives or clan links in the area continue to live in the open, or under trees.

The agency blamed insecurity in parts of Mogadishu, which has continued to jeopardize humanitarian access to the Somali capital, and surrounding regions, making the plight of civilians all the more desperate.

"UNHCR has additional stocks for up to 5,000 families in Mogadishu and smaller quantities in the town of Marka. However, we are still facing difficulties in bringing items out of the warehouses for distribution to thousands of families who fled from the capital to the adjacent provinces of Middle and Lower Shabelle, " it said.

About 128,000 Somalis are believed to have fled from Mogadishu since the beginning of February when the Ethiopian-backed transitional government ousted the Supreme Council of Islamic Courts (SCIC) from Mogadishu.

Nearly 90,000 of them have sought safety in the adjacent provinces of Middle and Lower Shabelle and an estimated 18,000 people have settled in the district of Afgooye.

"As the area has grown increasingly crowded, new arrivals are now compelled to move further north, notably towards the towns of Baidoa and Balcad," it said.

The UNHCR statement comes as UN Office for the Coordination of Humanitarian Affairs (OCHA) reported that aid workers are being thwarted in their efforts to assist internally displaced persons in Mogadishu and other vulnerable groups by the deteriorating security situation, harassment, intimidation and even detention.

Relief providers are further hampered by the difficulty in accessing aid supplies in Mogadishu because of the military's presence and activities.

Southern and central regions of the country have been hard hit by unprecedented droughts, flooding and three waves of intense fighting within the last year, further compounding the critical humanitarian situation in the country.

Hundreds of civilians were killed last month and more than 1, 000 wounded were registered in the city's two main hospitals.

Source: Xinhua