Evin prison. Photo: Wikipedia.

A 32-year-old Iranian-American pastor is being held at Iran’s notorious Evin Prison without notice of formal charges while his family mounts a campaign to secure his release.

The Reverend Saeed Abedini, a naturalized U.S. citizen and Christian convert, was arrested in September while visiting his family in Iran.

“When he became a Christian, he became a criminal in his own country. His passion was to reach the people of Iran,” Naghmeh, his wife, told Fox News.

Abedini is one of the leaders of the underground church movement in Iran. Made up of Christian converts, the movement claims to operate more than 100 churches in 30 Iranian cities, with more than 2,000 members.

However, the Iranian government sees the movement as a threat.

“It was just growing so fast. They see the underground churches as a threat and they see Christianity as a tool from the West to undermine them,” Naghmeh said. “They think if the country becomes more Christian, they are no longer under Islamic authority. That’s why it’s a threat.”

Under Shariah law, a Muslim who converts to Christianity in some cases can be punished by death. The Iranian government is especially harsh to Muslims who have converted to other faiths.

The American Center for Law and Justice (ACLJ) is working with the U.S. government to secure Abedini’s release.