CAIRO (AP) — Two leading human rights groups on Thursday accused Egyptian authorities of failing to conduct an impartial and transparent investigation into the suspicious death of an economic researcher in custody.

In a joint statement, Human Rights Watch and Amnesty International accused Egyptian prosecutors of having turned a blind eye to “mounting evidence” that 48-year-old Ayman Hadhoud disappeared, was tortured, and was denied access to timely healthcare.

Hadhoud’s whereabouts were unknown for two months before he was pronounced dead in April. The Interior Ministry said then that he had died in the government-run Abbasiya Mental Health Hospital in Cairo where he was brought for allegedly attempting to break into an apartment in the upscale Zamalek district of Cairo and exhibited “irresponsible behavior.”

His suspicious death had raised alarm among local and international rights groups especially after his family alleged that his body had facial bruises and a cracked skull.

“The severely flawed investigation into the causes and circumstances of Ayman Hadhoud’s death in custody is another stark reminder of the impunity crisis in Egypt,” said Philip Luther, Middle East and North Africa Research and Advocacy Director at Amnesty International. “Failure to adequately investigate and ensure accountability for his suspicious death only emboldens security forces to continue violating detainees’ right to life with no fear of consequences.”

Last month, an Egyptian court rejected an appeal filed by Hadhoud’s family to reinvestigate the evidence and the circumstances of his death. The court upheld the prosecutors’ decision to close the case and to rule out any criminal suspicion.

Earlier, prosecutors had refused demands to allow independent observers to attend the autopsy of Hadhoud’s body, and ultimately concluded that had died of chronic heart disease that led to a cardiac and respiratory arrest.

“Prosecutors have systematically neglected to investigate allegations of enforced disappearance and torture, and have admitted confessions extracted under torture as evidence in trials,” read the statement.

Both advocacy groups claimed that they had obtained leaked documents from the hospital showing that Hadhoud’s health was deteriorating while in custody. However, authorities failed to transfer him promptly to a better-equipped medical facility where his life could have been saved, the groups said.

Torture and abuse by police are not unusual in Egypt. In 2016, Giulio Regeni, an Italian doctoral student, was found dead on the side of a Cairo road. His body had been brutalized, raising suspicions of police involvement. Italy accused police officers of killing him, a charge that Egypt denied.