A Christian imprisoned in Iran may face years more in prison because of a new complaint.

According to Iranian Christian publication Mohabat News, Pastor Farshid Fathi may face an additional two years in prison after the imam of ward 10 of Rajaei-Shahr prison, where he currently serves his sentence, lodged a complaint alleging he insulted the religious authority.

A Christian prisoner in ward 10 told Mohabat News that the new lawsuit against Pastor Fathi stemmed from the imam's order to confiscate the Bibles that they had in their cells.

"The imam of our ward, called Mr Mortazavi, arbitrarily issued an order to confiscate our Bibles for inspection. Since we had received our Bibles with legal permission from the Superintendent of the prison, we refused to hand them over to the imam," the prisoner recalled.

The prisoner described the imam as very disturbed by the Christians' opposition, and proceeded to file a charge against Pastor Fathi for alleged insults.

"This may result in an additional two year prison sentence for him," he added.

Iranian law assigns an imam to each ward in the country's prisons. The Mohabat News noted that these imams have no legal authority to inspect or punish prisoners.

Aside from this new complaint, Pastor Fathi was sentenced to an additional year in prison in December after he was accused of possessing alcoholic beverages inside the prison. The pastor has denied the accusations and appealed the ruling. He is currently awaiting the decision of an Iranian appeals court.

Pastor Fathi is one of the many Christian pastors that were arrested on December 26, 2010 during a crackdown by the Iranian government. He is currently serving a six-year sentence, and was first incarcerated in Iran's infamous Evin Prison before being transferred to Rajaei-Shahr in August.

Evin prison has a notorious reputation for the torture, rape and brutal interrogations of inmates. Fathi himself described "mental torture" from his interrogators in a letter in 2013.