Separately, two loud explosions rocked a western sector of Tripoli on Sunday as jets flew overhead, witnesses told the AFP news agency.
An international coalition began carrying out attacks on forces loyal to Muammar Gaddafi, Libya's long-time ruler, on March 19, under a UN mandate to protect civilians in the country. NATO took command of operations over Libya on March 31.
"NATO struck weapons depots five minutes ago in an area which lies about 30km southeast of Zintan," Abdulrahman, the rebel spokesman, told the Reuters news agency by telephone on Sunday.
"We heard a loud explosion ... I think the strike hit some of them [the depots].
"We are now at a cemetery burying 11 people martyred during yesterday's fighting, in which 35 other fighters were also wounded."
The reported air raids came a week after the Libyan government said that Gaddafi's son, Saif al-Arab Gaddafi, and three of his grandchildren were killed in a NATO air strike on a compound in Tripoli.
Elsewhere in the country, rebels in the contested city of Misurata clashed with government forces near the airport, a rebel spokesman told the Reuters news agency on Sunday.
"Fierce fighting is taking place now at the airport and in the air force college area [near the airport]. We are still hearing sounds of artillery and rockets," the spokesman, called Abdelsalam, said from Misurata.
"NATO struck an area in the east of Misurata today but we do not have details."
Fuel depots destroyed
Misurata is the last remaining city in Libya's west under rebel control. It has been under siege for more than two months and has witnessed some of the war's fiercest fighting.
On Saturday, a rebel spokesman in Misurata said that Gaddafi's forces dropped bombs on four large oil-storage tanks, destroying them and sparking a fire that spread to four more.
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Government forces used small, pesticide-spraying planes for the overnight attack in Qasr Ahmed close to the port, Ahmed Hassan, the spokesman, said.
"Four tanks were totally destroyed and huge fire erupted which spread to the other four. We cannot extinguish it because we do not have the right tools," he said.
"Now the city will face a major problem. Those were the only source of fuel for the city. These tanks could have kept the city for three months with enough fuel."
Commenting on the latest fighting, Al Jazeera's Hoda Abdel-Hamid, reporting from the rebel stronghold of Benghazi, said on Sunday that Libya "is showing that it is ready for any kind of foreign aggression.
"They know that it is extremely important to keep the momentum in what appears now to be a very long and protracted conflict".
Meanwhile, Tunisia warned on Sunday that the repeated shelling from Libya of one of its border towns may force it to take measures to protect its sovereignty.
The country's official TAP news agency said that about 80 shells from Libya had fallen on Tunisian territory.
There were no reported injuries after the shells fell as Libyan troops fought with rebels to regain control of the Wazen-Dhehiba border post.
TAP quoted the Tunisian foreign ministry as warning that the country would take "all measures needed" within the law to ensure protection of its citizens, refugees and its territory.
Tunisia summoned Libya's ambassador on April 29 to complain after shells fell in inhabited areas. It now says Libya is not keeping to its commitments.
Meanwhile Italian coast guards and local fisherman saved all 528 refugees on a boat from Libya after their vessel hit rocks off the island of Lampedusa in an operation a rescuer described as a "miracle."
Among the refugees who had thrown themselves into the water at night were 24 pregnant women.