RAS JDIR CAMP, Tunisia The United Nations refugee agency is seeking satellite imagery of Libya that might explain the dramatic decline in the flow into Tunisia of migrants feeling violence in Libya, an official said.
"We don't understand why the figures have so significantly dropped overnight," UNHCR team leader Ayman Gharaibeh told Reuters on Sunday.
"We're getting different interpretations. What we know is that the numbers have gone down from 12,000 a day to 2,000 a day. So something dramatic must have happened on the other side of the border."
"We're trying to get more organized, to be prepared in case there is another influx," Gharaibeh said.
"We're trying to coordinate with governments that have the capability to try and give us any kind of satellite imagery that would help us plan better and to try to assess what could be the size of that influx."
Huge numbers of migrant workers have been fleeing Libya since violence broke out last month.
Opponents of Libyan leader Muammar Gaddafi say his forces attacked unarmed people protesting against his rule, while Gaddafi says al Qaeda operatives backed by foreign powers are trying to destroy the country.
Britain's International Development Secretary Andrew Mitchell, who has toured the area, said he had concerns about security on the Libyan side.
"I met people on the border who had been robbed by Gaddafi loyalists..., who said they had had in some cases their papers removed, any money they had, their watches, their goods," he told Reuters.
"This underlines the lawlessness and repulsive nature of the regime," he said on the sidelines of a Conservative Party meeting in Wales.
Britain sent planes to Tunisia as part of an international effort to evacuate thousands of Egyptian workers who fled the violence in Libya. British planes have flown more than 6,000 Egyptians back home and will repatriate 500 Bangladeshis stranded in Tunisia, Mitchell said.
The UNHCR and Tunisian army set up a transit camp last week capable of accommodating up to 20,000 for short spells while governments organized repatriation flights and ships for tens of thousands of Egyptians, Bangladeshis, Vietnamese and other migrant workers from Libya.
More than 105,000 have entered the country, including some 45,000 Egyptians, and 10 flights due at Tunisia's Djerba airport on Sunday were due to take the last of them home to Cairo.
But Bangladeshis, Nigerians and Ghanians are languishing in the camp for a fourth night, impatient for news of their evacuation.
The capacity of the transit camp could be scaled up "but there is talk of much larger migration numbers inside and I don't think this side will be able to bear with those numbers," Gharaibeh said.
Tempers were beginning to fray at the litter-strewn refugee camp, despite the steady arrival of what appeared to be adequate supplies of food and water, mainly from Tunisian charity and aid organizations.
The main highway from Tunisia to the Libyan border was choked with buses and pickup trucks loaded with aid or refugees and toilet facilities were overwhelmed.
"We just use the field," a man said. "It's cleaner."
(Additional reporting by Adrian Croft in Cardiff)
(Editing by Michael Roddy)