Chinese officials blamed poor management and inadequate precautions for an explosion . Explosion killed 104 and hospitalized 60 others . Comment: Four miners still trapped underground , state media reported .
Chinese officials blamed poor management and inadequate precautions for an explosion . Explosion killed 104 and hospitalized 60 others . Last year , 3,200 people were killed in mine accidents , state media said . Four miners still trapped underground , state media reported .