* Gaddafi wife, two sons, daughter flee to Algeria
* Rebels say son Khamis killed
* Tripoli residents shop for Muslim feast after Ramadan
(recasts, updates throughout)
By Samia Nakhoul
TRIPOLI, Aug 29 (Reuters) - The wife of Muammar Gaddafi and other members of his family took refuge in Algeria on Monday but the whereabouts of the fugitive former strongman himself remained a mystery, a week after rebels drove him from power.
Algeria’s Foreign Ministry said Gaddafi’s wife Safia, his daughter Aisha and his sons Hannibal and Mohammed had entered Algeria on Monday morning.
The development threatened to create a diplomatic rift as the rebel National Transitional Council (NTC) worked to consolidate its position as Libya’s new government.
An NTC spokesman accused Algeria, Libya’s western neighbour, of an act of aggression and said the council would seek the Gaddafis’ extradition.
A senior rebel officer also said Gaddafi’s son Khamis, a feared military commander, had been killed in a clash outside of Tripoli. The report could not be independently confirmed.
Meanwhile rebel forces converged on Gaddafi’s hometown of Sirte from east and west, intent on seizing one of his last bastions of support either by force or by negotiation.
Muammar Gaddafi’s whereabouts have been unknown since Tripoli fell to his foes and his 42-year-old rule collapsed a week ago after a six-month uprising backed by the West and several Arab nations.
The U.S. government said on Monday it has no indication that Gaddafi had left Libya. “If we knew where he was, we would pass that on to the opposition forces,” a White House spokesman said.
Algeria’s acceptance of Gaddafi’s wife and relatives angered the rebel leadership, who want him and his entourage to face justice for years of repressive rule and fear that he could orchestrate a new insurgency unless he is captured.
“We have promised to provide a just trial to all those criminals and therefore we consider this an act of aggression,” spokesman Mahmoud Shamman told Reuters. “We are warning anybody not to shelter Gaddafi and his sons. We are going after them...to find them and arrest them.”
Gaddafi strongholds in Sirte and some towns deep in the southern desert remain a challenge for Libya’s new rulers.
NTC chairman Mustafa Abdel Jalil asked NATO to keep up its air campaign, which has given essential firepower to the rebels.
“I call for continued protection from NATO and its allies from this tyrant,” he said in Qatar, a wealthy Gulf Arab state that has backed the revolt. “He is still a threat, not just for Libyans but for the entire world.”
NATO warplanes have struck at Sirte, on the Mediterranean coast, in recent days and Britain said its aircraft also attacked the artillery of Gaddafi forces near Sidra, west of the oil town of Ras Lanuf.
Whether or not Gaddafi makes a last stand in Sirte, the city is a strategic and symbolic prize for Libya’s new rulers as they tighten their grip on the vast North African country.
Rebel forces were advancing towards Sirte from east and west even as contacts continued for its surrender. The eastern column had pushed past the village of Bin Jawad and secured the Nawfaliya junction, a spokesman said.
Marwan Mustapha, an ambulance worker at Nawfaliya, said: “God willing, the rebels will enter the city without bloodshed and the negotiations will have succeeded. But if they have to enter by force, there will be blood.”
In the desert to the south, Gaddafi loyalists are also holding out. NTC military chief Suleiman al-Obeidi said pro-Gaddafi commanders in the city of Sabha had been in touch.
The death of Gaddafi’s son Khamis, if confirmed, would also harm his chances of a military fight back.
Colonel Al-Mahdi Al-Haragi, chief of the rebels’ Tripoli Brigade, said he had confirmation that Khamis was badly wounded in a clash near Ben Walid, west of the capital.
He was taken to hospital but died of his wounds and was buried in the area, Al-Haragi said, without giving the timing.
A U.S. official said Washington could not yet independently confirm Khamis’ death but similar information was being received in Washington from “reliable sources”. Khamis has already been reported killed twice during the uprising.
Earlier on Monday, prosecutor Luis Moreno-Ocampo of the International Criminal Court said he may apply for an arrest warrant for Khamis.
Human Rights Watch said members of the Khamis Brigade, which he commanded, appeared to have carried out summary executions of prisoners whose bodies were found in a warehouse in Tripoli.
The Hague-based ICC has already approved arrest warrants for Muammar Gaddafi, his son Saif al-Islam, and intelligence chief Abdullah al-Senussi on charges of crimes against humanity.
Mindful of preserving their image to the world and stung by accounts that captured Gaddafi loyalists have been found dead with their hands tied behind their backs, NTC leaders urged their followers not to abuse prisoners.
The NTC, now recognised as Libya’s legitimate authority by more than 40 nations, was working to establish control in Tripoli after days of chaos and clashes with hold-out Gaddafi loyalists.
The council, whose leaders plan to move to Tripoli from Benghazi this week, is trying to impose security, restore basic services and revive the energy-based economy.
Gunfire echoed occasionally across the city but aid agencies reported a revival of medical and other services.
Residents, hit by shortages of food, fuel and water, ventured out to shop amid the stink of garbage before the Eid al-Fitr festival after the Muslim fasting month of Ramadan.
“Thank God this Eid has a special flavour. This Eid we have freedom,” said Adel Kashad, 47, an oil firm computer specialist who was at a vegetable market. “Libya has a new dawn.” (Reporting by Samia Nakhoul and Mohammed Abbas in Tripoli, Maria Golovnina in Abu Grein, Alex Dziadosz in Nawfaliya, Robert Birsel and Emma Farge in Benghazi and Regan Doherty in Doha; Writing by Angus MacSwan; Editing by David Stamp)