An investigation has been launched into the attack, in which at least 125 people died

Grieving relatives are asking why safety standards within the underground system were not better

And there were earlier angry scenes as victim's relatives jostled police during the South Korean prime minister's visit

Soldiers are continuing the grim task of recovering bodies...

....as there are still many who remain missing

Many of the victims suffocated from noxious fumes - photographed here by a survivor on another train...

And the station floor still shows the marks of hands and nails as victims desperately struggled to escape