Is there a Sharia-prescribed punishment for someone who views pornographic images on the internet?

Allah commanded the believing men and women to lower their gaze, for the gaze is the messenger of the heart, and guarding it protects the heart from sins. It is reported in the Hadith that the gaze is a poisoned arrow from the arrows of Iblis, and whoever abandons it out of fear of Allah, He will replace it with a faith whose sweetness he finds in his heart. Looking at what Allah has forbidden is a sin that may lead to greater sins, but the Shari'ah has not specified a particular punishment merely for an unlawful gaze.