The first two pictures show victims recovered from a burning factory. Complete charring is not the role in most of cases of bodies recovered from fire. Charring is not an excuse for not doing a complete autopsy. Internal organs espicially the trachea and oesophagus are usually less affected by fire and the presence of soot in the trachea provide evidence that the victims were alive when the fire broke out. (As shown in pics 3 & 4)
Extensive heat leads to coagulation of muscle proteins and shortening of muscle fibers with a resultant flexion of big joints (pictures 1 & 2) imparting a pugilistic attitude of the cadaver.