Aides to former Libyan strongman Muammar Gaddafi who crossed into Niger were being detained, a US official said on Wednesday, urging other nations in the region to deny refuge to any wanted Libyans.
None of those crossing into Niger earlier this week appeared to be on a list of persons subject to United Nations sanctions, said State Department spokeswoman Victoria Nuland.
"Our understanding is that the convoy included some military and senior officials under Gaddafi's former regime," she said. "They are now being held in the capital... and they are being monitored closely by Nigerien officials."
Nuland said that based on information supplied by Niger to the US ambassador, the group included some 20 to 25 people and that reports of a massive convoy of 200 cars were "overblown."
Niamey was in contact with Libya's National Transitional Council on what to do with the Libyans, she added.
Libya's new rulers are anxious to arrest Gaddafi and put him on trial, thus sealing their hold on the country.
Niger was adamant Gaddafi was not aboard the convoy, and Washington made similar comments on Tuesday.
The United States, in addition to working with Niger, "is in contact with Mali, Mauritania, Chad and Burkina Faso to emphasize the importance of respecting the UN Security Council resolutions and of securing their borders," Nuland said.
Washington is "calling on all of these countries to make every effort to control their borders, to detain any Gaddafi regime officials, to confiscate contraband and any illegal weapons, to disarm them and also to confiscate any wealth that might properly belong to the Libya people."
Gaddafi's remaining forces have been a given a Saturday deadline to surrender, in a bid to spare further bloodshed.
Bidding to cut off Gaddafi's potential escape routes, the now-ruling NTC said it had dispatched a team to Niamey.