Kidnapping for ransom

Dear PAO,

If a person was detained and his captors, who are private individuals, asked for money from the relatives of the captive in exchange for releasing him, but the relatives did not heed their demands and the captive was released the next day, can the captors still be charged with kidnapping? The captors are claiming that they cannot be charged with kidnapping, but only with slight illegal detention, because their purpose was allegedly not attained considering that they did not receive any ransom. Is that correct? Please advise.