Source: http://news.bbc.co.uk/2/hi/europe/4107524.stm
Members of the convent in north-east Romania claim Maricica Irina Cornici was possessed and that the crucifixion had been part of an exorcism ritual.
Cornici was found dead on the cross on Wednesday after fellow nuns called an ambulance, according to police.
A priest and four nuns were charged with imprisonment leading to death.
Orphan
Police say the 23-year-old nun, who was denied food and drink throughout her ordeal, had been tied and chained to the cross and a towel pushed into her mouth to smother any sounds.
A post-mortem is to be carried out, although initial reports say that Cornici died from asphyxiation.
Local media reports that the young woman had arrived at the remote convent three months before, having initially gone there to visit a friend and opted to stay.
She grew up in an orphanage in Arad, in the west of Romania.
Mediafax news agency said Cornici suffered from schizophrenia and the symptoms of her condition caused the priest at the convent and other nuns to believe she was possessed by the devil.
"They all said she was possessed and they were trying to cast out the evil spirits," police spokeswoman Michaela Straub said.
Father Daniel who is accused of orchestrating the crime is said to be unrepentant.
"God has performed a miracle for her, finally Irina is delivered from evil," AFP quoted the priest as saying.
"I don't understand why journalists are making such a fuss about this. Exorcism is a common practice in the heart of the Romanian Orthodox church and my methods are not at all unknown to other priests," Father Daniel added.
If found guilty of killing Cornici, Father Daniel and the accused nuns could face 20 years in jail.