Tripoli, Libya (CNN) -- The nightmare in Libya's war-torn city of Misrata intensified Monday amid more shelling on the city and desperate measures to get medical care, an opposition spokesman said. "The aid coming from outside is not enough. There is no hospital," said the spokesman, who wanted to be identified only as "Mohammed" for safety reasons. He said 23 people were killed and 104 were injured in shelling Sunday in Misrata. Another person was killed and nine were injured Monday, Mohammed said. "The shelling and destruction by Gadhafi's forces has not stopped since yesterday," he said. "They are shelling mortar shells, cluster bombs and splinter mortar shells. The splinter mortar shells explode and throw lethal shrapnel, which has caused most of the tragedies."
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NEW: Death toll up to 24 Sunday and Monday, a witness says
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NEW: Misrata residents are "let down by NATO," a witness says
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U.N. official: Gadhafi's regime gave "no guarantees at all that the violence would cease"
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Britain to help 5,000 escape Misrata
Meanwhile, a British official met with @placeholder leaders Monday to discuss the humanitarian crisis in Libya.