Fears for safety of two Egyptian journalists after disappearance
Hassan al-Banna and Mostafa al-Aasar were travelling through Cairo on Sunday when they went missing.
Their families began a desperate search in hospitals and police stations to find the two journalists.
Banna's family received word from an unofficial source that the al-Sharouk newspaper intern was being held at Cairo's infamous security headquarters in the capital's Sheikh Zayed district.
The families have reached out to authorities for information on their whereabouts but to no avail.
Hassan's brother Abdelrahman Fares said on Facebook that he fears for the journalist's safety in custody as he suffers from health problems.
This could be fatal if he is subjected to torture or harsh conditions.
"Hassan al-Banna suffers from various diseases and he is on regular medicines, which his health depends on," he wrote.
"Hassan is physically weak and his body not capable of dealing with any torture or harsh conditions of detention."
President Abdel Fatah al-Sisi and the interior ministry would be held responsible for the safety and health of his brother, he added.
Human rights groups have documented systematic torture in Egyptian prisons with many cases ending in death.
Human Rights Watch reported prisoners are sometimes subjected to harrowing "assembly line"-style torture techniques, with detainees passing through routine sessions of beatings, electrocutions and sometimes rape.
Egypt is also under pressure to reveal the truth about murdered Italian student Giulio Regeni whose mutilated body was discovered dumped in a Cairo street.
Investigations revealed Regeni was likely subject to days of torture before his death, which would have included electrocution, stabbings and beatings. His body was found with cuts, bruises and broken bones.
Cairo has strongly denied any role in his killing, but anonymous security sources have revealed to media that Regeni was spotted in police custody shortly before his death.