An Egyptian atheist is in “serious danger” following his arrest and assault after protestors threatened to kill him and burn down his house in connection to the dissemination of a film insulting the Prophet Mohammed, his lawyer has warned.

Alber Saber, a 27 year-old blogger and computer science student from Cairo, is accused of defaming Islam — an antiquated legal charge that has seen a partial revival in a post-revolution Egypt dominated by Islamist groups.

Saber’s lawyer, Ahmed Ezzat, explained how his client’s ordeal began last Wednesday when a rumor spread that he had posted a trailer of the film “The Innocence of Muslims” — which portrays the Prophet as a thug and child molester and has sparked angry protests around the world — on an atheist Facebook page.

“With the famous film, the situation is very tense at the moment and many people in the neighborhood said that he had posted the film online and burned the Quran,” Ezzat told me from Cairo.

Saber’s mother, Kariman Mesiha Khalil, called the police and asked them to protect her son.

“I was not scared for myself; I was scared for my son. They were coming to butcher him,” she said.

When the police finally arrived, instead of protecting Saber, they arrested him.

According to Ezzat, Samer was transported to a local police station and thrown in a crowded jail cell. The guard on duty took his time to silence the rest of the inmates, informed the entire room that Saber had insulted the Prophet, locked the door, and left.

Saber was attacked by several prisoners, one of whom held a razor blade to his throat.

“He could have inflicted a serious injury,” Ezzat said. “We believe Saber is in serious danger. The public prosecutor will not tell us where he is being kept. No one knows where he is.”

“Innocence,” the crudely-made, amateur film trailer reportedly produced in the United States by a Coptic Christian fraudster, has sparked mass protests across the Middle East and in many countries with sizeable Muslim populations outraged at its portrayal of the Prophet Mohammed. Several US diplomatic mission buildings have been stormed, including the US consulate in Benghazi, where US Ambassador to Libya Christopher Stevens was killed.

In Egypt, demonstrators clashed with riot police for several days around the US embassy compound in central Cairo. More than 200 people were arrested and dozens wounded in the skirmishes.

Authorities blocked online access to the video throughout Egypt, but not before a prominent, ultra-Conservative Sheikh, Khaled Abdullah, aired a segment on the Saudi-backed Al-Nas [The People] channel last week.

Abdullah defended his decision to air the trailer and continues to host his show although a civil lawsuit has been filed against him. The contrast between the treatment of Abdullah and Saber could not be more pronounced.  

While Ezzat denies his client ever posted the trailer for the controversial film online, police investigators uncovered a video, made by Saber and entitled “Why Did God Create Man?” which  questions the notion of religious authority.

“The video criticized [religious] leaders for how they think that they hold all the truths and everyone else is false,” Ezzat explained. “Our defense is freedom of expression.”

Saber was refused bail and ordered to spend the next two weeks in custody at a secret location. Meanwhile, the mob returned to his home.

They surrounded the building and ordered his mother to leave the neighborhood or be burned alive inside the flat. Khalil, who is a Coptic Christian, has been in hiding since the weekend. She spoke to me from a safe house.

“I can’t go back to the area and I don’t have anywhere to stay now,” she said. “This is not ordinary. My son didn't do anything. He's a very good guy and he has friends from all religions. This is throwing wood on to the fire but to what purpose? I don't know.”

Trials of those accused of insulting Islam have made a return to Egyptian courts in recent months.

In February, a charge of insulting Islam against billionaire tycoon Naguib Sawiris — who had posted images of Mickey and Minnie Mouse in traditional Islamic garb on his Twitter feed — was thrown out of court.

Three months later, a Christian teenager was sentences to three years in prison after posting a drawing mocking the Prophet on Facebook. On Tuesday, a teacher was sentenced to six years in jail – three for insulting the Prophet – at a court in southern Egypt for a similar offence. Such cases are numerous; only the highest profile trials receive much coverage.

Lawyers and rights activists have criticized the rash of lawsuits brought against citizens they say are merely expressing their opinion. Local support for Saber has been anemic, possibly due to the fact that atheism in Egypt remains largely taboo.

“The public prosecutor, who is a religious man, took me aside and angrily asked me how I could defend such a person who didn’t believe in God. I said: ‘He is a citizen and he has the right to express his opinion’,” Ezzat said.