Unidentified assailants set fire to an Egyptian Coptic Church in Libya's city of Benghazi on Thursday as contoversy continues over the death of Ezzat Attallah, an Egyptian Christian who died in Libyan prison after he was arrested for proselytizing his faith.

Witnesses described seeing flames rise from the church used by Egyptian Christians, according to The Associated Press.

On Thursday, Reuters news agency also published photos of black smoke rising from windows of the church, which was target of an attack weeks earlier.

In a statement, the Egyptian Foreign Ministry condemned what it called an "assault."

Security forces stopped the unidentified assailants before they could cause more damage to the building. 

Benghazi security official Abdel-Salam al-Barghathi said the assailants were angry about a protest in Egypt this week over Attallah's death.  

Attallah was among some 5 evangelical Egyptian Christians and dozens of Christians who were detained in February for allegedly spreading Christianity in the predominantly Muslim country Libya.

There is strong disagreement over what caused Attallah to die while in prison. While the Egyptian Foreign Ministry claims he died from poor health due to diabetes and heart ailments, Christians in Egypt believe poor prison conditions and possibly torture caused his death. 

On Monday, more than 100 protesters gathered at the Libyan Embassy in Cairo, chanting: "It is illegal to kill Copts."