RAMALLAH - A human rights group has submitted an appeal to Israel's courts to allow doctors to visit hunger-striking prisoner Bilal Diab.

Physicians for Human Rights submitted an appeal based on the recommendation of Ahmad Tibi, a Palestinian member of the Israeli Knesset.

"After 68 days on hunger strike, Bilal Diab’s medical condition has become serious and he must be checked by a doctor from outside the prison service," a statement from the group said.

A report from Tibi was attached to the appeal.

Bilal Diab, 27, from Jenin, and Thaer Halahla, 33, from Hebron -- are in a precarious condition after 68 days without food, a doctor from Physicians for Human Rights-Israel said on Wednesday.

It was only the second visit to the hunger-strikers since they began refusing food on Feb. 29, after a legal petition was filed to gain access to the detainees, the prisoners group Addameer said.

On Thursday, Diab reportedly collapsed in court and was examined by Israeli MK Ahmad Tibi, who is a physician.

The prosecution claim that the prisoner represents a threat to the security of Israel.

Diab and Halahla are among over 300 Palestinian detainees held in Israeli jails in administrative detention without charge or trial.

Human Rights Watch on Wednesday called on Israel to "immediately charge or release people jailed without charge or trial under so-called administrative detention," in a statement.