US intelligence and military officials say no one can be sure who controls the Libyan government's weapons stockpiles.
They range from tonnes of mustard gas and raw nuclear materials to 30,000 rockets.
Officials say the stockpiles still appear to be under Libyan government control, despite the rebel takeover of the capital of Tripoli.
They say that may or may not be good news, depending on whether troops still loyal to Colonel Gaddafi honour international agreements not to use the material.
One fear is that pro-Gaddafi forces might use the weapons to make a last stand, or that al-Qaeda may acquire them.
NATO says its planes have been in action all over Libya in the past 24 hours, reaching a milestone of 20,000 sorties since the start of the rebel campaign on 16 February.
Meanwhile, foreign journalists who covered the conflict from Colonel Gaddafi's side remain trapped inside their hotel in Tripoli for a third day as gunmen still loyal to the regime keep them prisoner.
With electricity and water cut off and no staff, about 30 journalists are grouped on the first floor of the Hotel Rixos, wearing helmets and flak jackets and listening to the sounds of gunfire outside.
With stray bullets hitting the hotel, the correspondents have hung banners on the outside, reading ''Television, press, don't shoot''.
The National Transitional Council in Libya says 400 people were killed and 2000 wounded in the three days of fighting in Tripoli that finally toppled Colonel Muammar Gaddafi.
Chairman Mustafa Abdel Jalil told France-24 television that some 600 pro-Gaddafi fighters have been captured, but the battle will not be over until the dictator himself is a prisoner.
The council is seeking $US2.5 billion in international aid by the end of the month to help the country recover from the six month civil war.
NTC members are to meet representatives from the United States, France, Italy, Britain, Turkey and Qatar in Doha to discuss the subject.