An Iranian pastor acquitted of apostasy in September 2012 has been re-arrested today in Iran, along with his wife and a fellow church member, according to Christian Solidarity Worldwide (CSW).

Youcef Nadarkhani, a pastor in the Church of Iran, was first arrested in 2009 after he went to his children's school to question the Muslim monopoly on Iranian education, which he considered unconstitutional.

He was charged with apostasy and sentenced to death in 2010.

Despite being asked repeatedly in court hearings to renounce his faith in order to avoid the death penalty, Nadarkhani refused.

He was released from prison on 8 September 2012, following his acquittal on apostasy charges, though he was found guilty of evangelising to Muslims, for which he received three years.

Nadarkhani was arrested today in Iran alongside his wife, Tina Pasandide Nadarkhani, and a fellow church member, Yasser Mosayebzadeh.

"We are deeply concerned by these developments and await further clarification regarding the reasons for these arrests," said CSW's chief executive Mervyn Thomas.

This is not the first time Nadarkhani has been re-arrested. He was detained on Christmas day 2012 on the orders of the director of Lakan prison, where he had been held to serve the remainder of his three year sentence. He was released again on 7 January 2013.

"Unfortunately, it is not uncommon for Christians who have been arrested on account of their religious beliefs to be released and re-arrested time and again, in a tactic designed to foster a sense of insecurity within the community," Thomas said.

"We urge the authorities ensure Pastor Nadarkhani, Tina Nadarkhani and Yasser Mosayebzadeh receive due process, and once again call on Iran to fully respect its constitutional and international human rights obligations by ensuring that justice and equality before the law are guaranteed to all citizens, regardless of their religion or belief."