Forces loyal to Libya’s Moammar Gadhafi fired a barrage of rockets Friday at National Transitional Council fighters near Bani Walid.

The rocket attack follows days of negotiations between transitional representatives and tribal chiefs tied to Mr. Gadhafi. The incident took place a day before the NTC’s deadline for Gadhafi loyalists to surrender before NTC forces warn they of an assault on the desert town.

Meanwhile, a senior general and other officials who were part of Mr. Gadhafi’s government have crossed into Niger.

News organizations quote officials in Niger who say General Ali Kana and several other high-ranking officials were part of a group of about a dozen people who entered the country on Friday.

Kana was in charge of Mr. Gadhafi’s troops in southern Libya. He is a Tuareg, the dominant tribe in northern Niger.

On Wednesday, Niger’s justice minister said 18 people had entered the country from Libya in recent days, but that Mr. Gadhafi was not among them. Libya’s National Transitional Council sent envoys to Niger in an effort to prevent the fugitive former leader and his associates from leaving Libya.

Interpol has issued an arrest warrant for Mr. Gadhafi, his son Saif al-Islam and Libya’s former intelligence chief .

The international police agency said Friday that it issued a “red notice” calling on all countries to help locate the three men and place them under arrest. Their current whereabouts are unknown, but they are accused of committing crimes against humanity.

A Syrian television station aired an audio message Thursday that was said to have been recorded by Mr. Gadhafi, who denied he had crossed into Niger. The former leader denounced the NTC fighters who seized control of Tripoli and contended troops loyal to him are still able to mount a resistance to the new administration taking shape in Tripoli.

NATO said Thursday its warplanes bombed five armored vehicles near Mr. Gadhafi’s hometown, Sirte, as well as 18 surface-to-air missile systems around the town of Waddan, 300 kilometers to the south.

Near Bani Walid, a desert town held by Gadhafi supporters, negotiators from Libya’s National Transitional Council say they are committed to avoiding bloodshed as they press tribal elders tied to the former leader to surrender.