Magento: subcategory from a particular category

<?php
$_categoryModel = new Mage_Catalog_Model_Category();

$_subCategoryList = $_categoryModel->load(3)->getChildrenCategories();

foreach ($_subCategoryList as $category)
{
$cat=$_categoryModel->load($category->getId());
?>
<li><div><img src="<?php echo Mage::getBaseUrl('media').'catalog/category/'.$cat->getImage()?>"/><a href="#"><?php echo $cat->getName()?></a></div></li>
<?php
print_r($category);
}
?>