(CNN) -- Artillery shells slammed into a hospital Sunday in the northern Sri Lankan district of Mullaittivu, where civilians -- including a growing number of children -- are being treated as government forces and Tamil rebels continue to clash. A Sri Lankan soldier walks through Mullaittivu, the former military headquarters of the Tamil rebels. More than 200 civilians and at least 30 children have been injured in the last three days of fighting, a relief worker told CNN Sunday. "That is the absolute minimum (number of injured)," the aid worker, who did not want to be identified for fear of jeopardizing the work of relief organizations, said.
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Sri Lankan hospital hit by artillery shells
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Children young as 4 months treated in local hospitals for shrapnel injuries
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Aid workers rescue 50 critically injured children and 105 adults
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Sri Lankan President has promised to allow safe passage to trapped civilians
Sunday, Sri Lankan soldiers seized a key rebel stronghold in a surprise attack deep in @placeholder held territory.