Musnad Abu Ya'la al-Mawsili 140:49

Abdullah ibn Abd al-Samad narrated to us, Muhammad ibn Humayd narrated to us, from Ibn al-Mubarak, from Imran ibn Zayd, Yazid al-Raqashi narrated to us, from Anas ibn Malik, who said: I heard the Messenger of Allah, may Allah bless him and grant him peace, saying: "O people, weep; and if you do not weep, then feign weeping. For the people of the Fire will weep in the Fire until their tears flow upon their faces as if they were streams, until the tears cease and blood flows instead, and the eyes become ulcerated. If ships were launched into them, they would sail."