By Rabie al-Sukkari and Omar Thabet

CAIRO

The family of Mohamed Morsi, Egypt’s first freely elected president, has accused the Egyptian authorities of mistreating Morsi’s son Osama, who for the last three months has been held at Cairo’s notorious Aqrab prison.

"Osama is being subject to abuse in jail,” Abdullah, another of Morsi’s sons, said Monday on Facebook.

According to Abdullah, Osama has remained in detention since last December, when he publicly appealed to international organizations -- including the UN -- to intervene on behalf of his family, which has been prohibited from visiting the jailed ex-president for the last three and a half years.

Now members of Morsi's family are not being allowed to visit Osama in prison.

"Since Osama was detained, we have not been allowed to visit him or provide him with basic needs, such as clothes and food,” the family said in a statement.

"At a Feb. 25 trial session, Osama told his lawyer he was being mistreated inside the prison," the statement read, going on to hold the Egyptian authorities solely responsible for Osama’s health and safety.

Speaking to Anadolu Agency, an official source at Egypt’s prison authority denied the family’s allegations, describing them as “totally untrue”.

"Prison regulations apply to everyone without exception," the source, preferring anonymity as he was not authorized to speak to media, said.

“We cannot deprive any detainee of his basic needs,” he added.

"He [Osama] has been barred from receiving familial visits for security reasons," the source asserted without elaborating.

Egypt’s first-ever democratically elected president, Morsi was ousted and imprisoned by the army in a 2013 military coup.

He is now serving out three lengthy jail terms for "killing protesters" and "spying" for Qatar, while he continues to face charges of "insulting Egypt’s judiciary".

Morsi, along with a number of independent observers, say the charges against him are politically motivated.