The United Nations refugee agency says it is mounting an emergency airlift to eastern Chad this week to bring supplies for tens of thousands of Sudanese refugees.

The UNHCR says it has already flown into Chad some plastic sheeting, four transportable warehouses and some four-wheel drive vehicles. It has tons of blankets, kitchen sets, fuel canisters, soap and other relief supplies stockpiled in Tanzania.

UNHCR spokesman Ron Redmond says daily flights from Mwanza, Tanzania, to Abeche, Chad will deliver non-food supplies to an estimated 110,000 Sudanese refugees scattered along a 600 kilometer stretch of the Chadian border.

"The airlift coincides with an urgent refugee relocation operation aimed at moving tens of thousands of refugees away from that insecure Chad-Sudan border to safer camps further inland, before the start of the rainy season in May, at which time those left behind will be extremely difficult to reach," he said.

U.N. aid workers report several thousand refugees who fled bombing raids in the Darfur region of western Sudan at the end of January appear to be in good health, but are exhausted. However, they have found some cases of malnutrition among children.

Mr. Redmond says thousands of refugees are living in makeshift shelters, and they must be moved urgently to safer locations.

"We cannot find enough campsites with adequate water supplies to move people to," he said. "So, we continue with a team of five hydrologists to search for sites further inland, so that we can move these people away from the border, because there are also continuing reports of raids by bandits and militia from across the border in Sudan. They are coming across stealing their cattle and what little possessions they may have left."

Mr. Redmond says the UNHCR has transported nearly 4,000 refugees inland to new camps. He says it will be a race against time to move another 80,000 refugees to safety before the May rains begin and the roads become impassable.