Tripoli, Libya (CNN) -- Moammar Gadhafi's military machine pounded the western city of Misrata again Tuesday as France and Britain called for beefed-up NATO airstrikes to stop such attacks on the Libyan people. Witnesses reported heavy shelling in central Misrata, besieged for weeks and the scene of some of the worst fighting in the Libyan conflict. At least 10 people were killed and 30 others wounded in the heavy shelling, a doctor operating in two central clinics told CNN. The doctor, identified only as Dr. Hakim for safety reasons, said medical teams are exhausted from treating the wounded. Rebel fighter Moaath al-Misrati told CNN the shelling came after rebels killed several of Gadhafi's snipers. "We are expecting a ground offensive by the Gadhafi forces any time now," he said.
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NEW: Leading rebel official calls on international community to help Libyan civilians
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At least 10 killed in Misrata shelling, doctor says
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France and Britain call for intensified NATO attacks
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Ex-Foreign Minister Koussa flies to Qatar ahead of an international meeting
Meanwhile, @placeholder's most high-profile defector flew from Britain to Qatar Tuesday for talks on how to break the deadly impasse in his nation.
@placeholder, who fled Libya last month and sought safe haven in Britain after resigning his post in Gadhafi's regime, urged all parties to avoid plunging Libya into a civil war.