The United States does not believe that Libyan leader Muammar Gaddafi was among those entering Niger in a convoy, the State Department said on Tuesday.

Department spokeswoman Victoria Nuland said that U.S. ambassador in Niger had discussed the matter with Niger officials. "Apparently, a convoy has entered, and it does include some senior members of the Gaddafi regime, but we do not believe that Gaddafi himself was among them," she told reporters at a regular news briefing.

"We don't have any evidence that Gaddafi is anywhere but in Libya at the moment," she said, adding that the U.S. has not heard about Gaddafi's family members in the convoy.

Press reports said that a large convoy of civilian and military vehicles from Libya crossed into Niger late Monday. Local officials denied that Gaddafi was aboard.

Nuland noted that the U.S. has strongly urged Niger officials to detain the members of the Gaddafi government who may be subject to prosecution, and confiscate any weapons and state property that were found.

She said that the U.S. has been talking in recent days with all of Libya's neighboring states about their UN Security Council obligations.

Rebel troops in Libya are continuing their manhunt for Gaddafi after they captured his stronghold in Tripoli on Aug. 23.