Palestinian refugee Fadi Husain Amoura died under torture in a Syrian prison, bringing the total number of Palestinian victims of torture to more than 600 refugees, a human rights group has reported.

The Action Group for Palestinians of Syria (AGPS) said in a Tuesday report that Fadi’s family was recently updated on his death. He was a resident of Yarmouk refugee camp, in Damascus.

Fadi’s death brings the toll of victims of torture among Palestinian refugees in Syria to 617.

AGPS estimates the real number to be far higher due to the gag orders slapped by the Syrian government on the detainees’ names and fates, along with the families’ reluctance to report such cases over retaliation concerns.

Affidavits by ex-detainees have provided evidence on the involvement of Syrian government officers in harsh torture tactics, including electric shocks, heavy beating using whips and iron sticks, and sexual abuse against Palestinian prisoners, in a flagrant violation of the Convention against Torture and Other Cruel, Inhuman or Degrading Treatment or Punishment, commonly known as the United Nations Convention against Torture (UNCAT).

AGPS has urged the Syrian government to disclose the fate of scores of Palestinians held in its lock-ups, release the bodies of those tortured to death, to seriously work on halting harsh torture tactics, launch fact-finding probes into crimes of torture, and to bring those involved in such crimes before courts.