Barnabas Fund is appealing to the United Nations to intervene after India refused to grant refuge to six Afghan converts.
The converts were named only as Rahimullah and Rita, who have three children, another couple Mohammad and Aisha, who have two children, and two sisters Shazia and Sunita.
They fled to India after converting from Islam to Christianity, but now face being deported back to Afghanistan where they could be arrested and sentenced to death for apostasy.
Rahimullah and Rita have submitted an appeal application to the United Nations High Commission for Refugees in which they express their fears about returning home.
"As we are converted and baptized Christians, we are deeply fearful for our lives. In the light of the situation in Afghanistan, we will be sentenced to death and executed by the government or we could be stoned and burned by the people," they wrote.
Barnabas is appealing to the UNHCR to intervene in their case and is urging other people to show their concern by writing to the organization in support of the applications for refugee status.
The charity said the converts face "certain danger" if they return to Afghanistan, where there has been a crackdown on converts in the last year.
Dr. Patrick Sookhdeo, international director of Barnabas Fund, said: "The cases of these six dear brothers and sisters highlight the fact that Afghan converts to Christianity are safe neither inside nor outside the country. It is a disgrace that they have been denied refuge when their very lives depend on it."
Anti-Christian sentiment reached new heights after a TV documentary was broadcasted last May showing images of six Christians being baptized.
The footage led the deputy secretary of the Afghan Lower House of Parliament to openly call for the public execution of the Afghan Christians shown in the documentary.
One of the converts identified in the documentary, Said Musa, had been facing execution but was freed from prison yesterday after months of careful negotiations involving the U.S. and Italy.
Said's release was announced yesterday by another persecution ministry, International Christian Concern.
The charity's regional manager for the Middle East, Aidan Clay, said Musa had been released from prison although he could not confirm his whereabouts.
Another convert, Shoaib Assadullah, has been in prison for the last four months after giving someone a copy of the Bible.
In a letter smuggled out of the jail, Assadullah said he was under "severe psychological pressure" and had been attacked by fellow prisoners.
He expects his case to go before the courts soon and is preparing himself for the worst.
"The court's decision is most definitely going to be the death penalty for me, because the prosecutor has accused me under the Clause 139 of the criminal code which says, 'if the crime is not cited in the criminal code, then the case has to be referred to the Islamic sharia law,'" he wrote.
Barnabas Fund recently launched a letter-writing campaign against the arrest, imprisonment and execution of converts.
Dr. Sookhdeo said: "I am greatly moved by Shoaib's letter, which demonstrates his tremendous courage in the face of the death penalty. It underlines the urgent need for the international community to press for his release, and for the Afghan government to allow true religious freedom."