Beijing - In the latest development in Libya, explosions and anti-aircraft gunfire have been heard in the capital Tripoli.
Libyan state television reported that "civilian and military targets" in Tripoli and Tajoura had come under attack.
The US Defence Department said Thursday's attacks were conducted against Libyan air defence systems and other military targets.
Earlier, government spokesperson Mussa Ibrahim said Libya's telecommunications centres and state radio station would be targeted by a new round of air strikes. Mussa said nearly 100 civilians have been killed so far in the air strikes launched by major Western powers since Saturday.
He urged the United Nations to "stop any kind of action" against "civilian targets" that "affects the everyday life of the Libyan people".
US Secretary of State Hillary Clinton said on Thursday that the United States has agreed to hand over command of enforcing a no-fly zone over Libya to NATO.
"We are taking the next step -- we have agreed along with our NATO allies to transition command and control for the no-fly zone over Libya to NATO," Clinton said at the State Department, adding that all the 28 NATO allies have now "authorised military authorities to develop an operations plan for NATO to take on the broader civilian protection mission."
NATO Secretary General Anders Fogh Rasmussen told CNN on Thursday that "what we have decided today is that NATO will enforce the no-fly zone. We're considering whether NATO should take on that broader responsibility, but that decision has not been made yet."
"Without predicting the outcome of our deliberations, I think we might be able to take that decision within the coming days," he added.
Clinton also said that the coalition force is "in control of the skies over Libya."
Having eliminated Libyan air defenses, US military officials said the campaign has entered a second phase that will focus on decimating Libyan leader Muammar Gaddafi's ground forces. Coalition air strikes also increased over Tripoli, with warplanes targeting fuel depots and local military installations.
