Two Christians from the Church of Iran denomination, Behzad Taalipasand and Mohammadreza (Johann) Omidi, were detained on New Year's Eve in the northern city of Rasht.
The arrests are the latest developments in a December crackdown on house churches by the Iranian government.
In an annual ritual ironically referred to by local Christians as a "Christmas gift", the Iranian regime generally intensifies its campaign of repression during the Christmas season. In 2010, 70 Christians were arrested during this period, while in 2011, the authorities in the southern city of Ahwaz aided and detained an entire Assemblies of God (AoG) congregation, including the Sunday school children.
This year has been no exception. On 25 December Pastor Yousef Nadarkhani of the Church of Iran, acquitted of apostasy in September, was jailed again in Rasht at the instigation of prison authorities to serve the remaining 45 days of a three year sentence for evangelising Muslims.
Then on 27 December, around 50 Christians were arrested at a residential home in Tehran where they had gathered to celebrate Christmas. According to reports received by Iranian news agency Mohabat News, the majority were released after being interrogated and handing over mobile phones, full contact details and passwords to emails and social networking sites.
However, 60-year old Reverend Vruir Avanessian was detained in Evin Prison, despite suffering severe health challenges. The reverend has since been escorted by guards to a specialist clinic for compulsory dialysis treatment, where he was briefly visited by his wife before being returned to prison.
Also in December, news emerged of the imprisonment without charge since September of the Reverend Saeed Abedini, a 32-year-old dual Iranian and American citizen, who was detained while visiting his parents. According to reports the Reverend has been given several dates for a court hearing, which has been repeatedly postponed.
Mervyn Thomas, Chief Executive of Christian Solidarity Worldwide (CSW) said: "The Iranian government's annual campaign of arrest and harassment during a significant religious holiday is wholly unacceptable. As a signatory to the International Covenant on Civil and Political Rights (ICCPR), Iran is obligated to uphold freedom of religion or belief for all of its citizens, and this must include the right to observe days of worship and manifest their belief in communion with others.
"Moreover, while it is good that Reverend Avanessian is being allowed to receive necessary medical treatment, CSW condemns his arrest and question Iran's continuing unwillingness or inability to provide adequate medical attention for Pastor Benham Irani, whose health continues to deteriorate in prison.
"It is vital that the Iranian government ends the harassment of religious minorities within its borders, respects their right to religious freedom, and releases immediately and unconditionally all who have been imprisoned on account of their faith."