National Transitional Council (NTC) fighters took full control of Sirte airport, Reuters witnesses said. They had taken it two weeks ago, but then lost it again. Sirte’s pro-Qaddafi defenders have used sniper, rocket and artillery fire to fight off two full-scale NTC assaults on the city in the past week. Each side has accused the other of endangering civilians. “They’re shelling constantly. There’s indiscriminate fire within individual neighborhoods and from one area to another,” Hassan, a resident who escaped the city, told Reuters.

Civilians have been fleeing Sirte, a coastal city of 100,000 that is also under NATO aerial attack, and Libyan authorities have asked the United Nations for fuel for ambulances to evacuate wounded, a UN source in Libya said.

The United Nations is sending trucks of clean drinking water for civilians crammed into vehicles leaving Sirte for Benghazi in the west or Misrata in the east, the source said.

But fighting has prevented UN aid workers from reaching Sirte and Bani Walid, another town held by Qaddafi loyalists.

“There are two places we’d really like access to, Sirte and Ben Walid, because of concern on the impact of conflict on the civilian population,” the source told Reuters in Geneva.

UN officials do not have any direct contact with pro-Qaddafi forces holed up in Sirte, where both sides accuse the other of cutting off water and electricity, he said.

Aid agencies said on Wednesday that a humanitarian disaster loomed in Sirte amid rising casualties and shrinking supplies of water, electricity and food.

Fighting on Sirte’s eastern and western approaches was less intense on Thursday than on previous days, but the NTC said it had cleared a route between the two fronts, allowing its forces to link up — a strategic boost along with retaking the airport.

US Senator John McCain, visiting Tripoli, said Qaddafi’s overthrow had set an example to people all over the world, adding that US investors were keen to do business with oil-exporting Libya once fighting there had stopped.

“We believe very strongly that the people of Libya today are inspiring the people in Tehran, in Damascus, and even in Beijing and Moscow. They continue to inspire the world — and let people know that even the worst dictators can be overthrown and be replaced by freedom and democracy,” he said.