Dr. Itai Pessach of Sheba Hospital in Tel Hashomer, who is in charge of medical treatment for the four Israeli hostages who were rescued on Saturday, told CNN in an interview on Monday that they were beaten while in Hamas captivity in Gaza.

“It was a harsh, harsh, experience, with a lot of abuse, almost every day,” he said, adding, “Every hour, both physical, mental, and other types, and that is something that is beyond comprehension.”

Pessach said the eight months spent in captivity “left a significant mark on their health” and despite appearing in good condition initially, they are all malnourished.

“They had no protein, so their muscles are extremely wasted, there is damage to some other systems because of that,” he told CNN.

Pessach said the hostages told him they were moved several times, dealing with a number of different guards. The supply of food and water was unstable.

There have been periods where they got almost no food whatsoever. There were other periods where it was a little better, but all in all, the combination of the psychological stress, malnutrition or not getting enough food or not getting the right kind of food, medical neglect, being limited to space, not seeing the sun and all of the other things have [a] significant effect on health.”

Dr. Pessach also treated some of the hostages released in the hostage release deal back in November. He told CNN that the psychological damage of these four is more intense due to the length of time they were held.

As time passes, hope of being released kind of decreases and you start wondering if this would ever end… losing that faith, I think, is where you get to the breaking point.”