Al-Jazeera reports three massive explosions just east of the Libyan city of Ajdabiya 150 kilometres south of Benghazi.
It says the Western-led coalition was bombing and rocketing forces of the Libyan leader Muammar Gaddafi.
The anti-Gaddafi rebels say they have taken advantage of the strike to fight their way to the central part of Ajdabiya.
The city is key for protecting Benghazi against Gaddafi attack.
Over the past 24 hours or so, the coalition has fired 16 Tomahawk cruise missiles at military targets of the Gaddafi regime.