NIAMEY/THE HAGUE: Niger’s army has clashed with a heavily armed convoy of vehicles that entered its territory from Libya, killing 13 in the convoy and suffering one casualty on its side, military sources in the West African country said Wednesday.

The sources said Nigerien authorities took a further 13 prisoners after the incident, which took place Sunday around the remote northern Nigerien mining town of Arlit just south of the border with Algeria.

“I understand it was a convoy of pro-Gadhafi Libyans guided by Malian Tuaregs,” said one army officer who declined to be named, adding that some members of the convoy had fled.

Niger’s government said late Tuesday there had been a clash, without specifying that the convoy had come from Libya, where forces loyal to slain leader Moammar Gadhafi have been routed by NATO-backed rebels now in control of the country.

The government statement said Nigerien forces had seized arms including 36 assault rifles, 11 machine guns, three rockets and over 11,000 cartridges of different calibers.

Hundreds of thousands have fled Libya south into Niger and neighboring Mali in past months. The vast majority are migrant African workers who had settled in Libya, but authorities have also signaled the return of some armed pro-Gadhafi fighters.

Niger has taken in Gadhafi loyalists including four generals and his son Saadi, saying it is sheltering them on humanitarian grounds. Niger has not commented on speculation that another Gadhafi son, Seif al-Islam Gadhafi, has sought to enter Niger.

However, it has said that if he did, it would fulfill its commitments to the International Criminal Court, which has issued an arrest warrant for him over alleged crimes against humanity.

The ICC prosecutor Luis Moreno-Ocampo told reporters Wednesday that the last time he had contact with Seif al-Islam was two weeks ago, and that he was still working with state parties on how to arrest him.

Libya’s interim leaders, the National Transitional Council, have said they would like to try Seif al-Islam in Libya.

Separately, Moreno-Ocampo said Wednesday he may charge Moammar Gadhafi’s spy chief, Abdullah al-Senussi, and others suspected of involvement in hundreds of rapes in Libya during this year’s conflict.

The Hague-based court has already indicted Senussi on charges of crimes against humanity and other war crimes.

Earlier this month, Moreno-Ocampo told the U.N. Security Council he was investigating whether the former Libyan leader, now dead, and his spy chief ordered mass rapes. “We have indications that Senussi was involved in organizing the rapes, but not Seif,” Moreno-Ocampo told Reuters.

In Tunis, an appeals court Wednesday rejected a request to free former Libyan prime minister Baghdadi al-Mahmudi, a day after approving his extradition, despite concerns expressed by rights groups and Mahmudi himself over his safety in Libya.