Zintan, Libya (CNN) -- Over the past two days, Moammar Gadhafi's forces have unleashed their biggest attack yet against one of the mountainous rebel strongholds in western Libya, according to one of his former generals. Haji Usama, as he is known to the rebels, was once a top commander in Gadhafi's forces. He spent decades in the Libyan army including a tour of duty in neighboring Chad, and now commands in Zintan, population 40,000. Today, he hates that his former commander in chief regards him as a terrorist. Haji Usama says that early Thursday morning about 150 of Gadhafi's infantry troops -- supported by about 40 vehicles, including long range "Grad" rocket launchers and heavy, long-range machine guns -- began an attack on three fronts near Zintan.
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Haji Usama was once a top commander in Gadhafi's forces
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He now commands in Zintan for the rebels
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He gives his account of major offensive in rebel stronghold
Haji Usama
Usama
Usama
Haji @placeholder admits many of his fighters are young, but he says "they are keen and determined to fight for their freedom."
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Zintan
Zintan
Zintan
As dusk fell Friday the shelling that could be clearly heard and seen from the roof tops of @placeholder earlier abated before picking up with sporadic barrages of fire shortly before 10 p.m.
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Zintan
Zintan
Zintan
The rebels say the night-time shelling is simply to terrorize @placeholder's residents into fleeing.