Former head of a crime organization Assi Aboutboul, who is jailed at the Sharon Prison, hurt himself on Thursday.
He was lightly wounded as a result of superficial cuts to his hands and was being treated at the prison's clinic.
The Prison's Service is investigating whether this was a suicide attempt or self harm.
Aboutboul is under arrest on suspicion of involvement in two murders in the early 2000s and in two attempted murders.