The Archbishop of Canterbury, Dr Rowan Williams, has added his voice to calls for an immediate end to the violence being waged against Christians in India's Orissa state.

Hindu extremists, some wielding machetes, have been on the rampage in the north-eastern state since the murder of Hindu leader Swami Lakshmananda Saraswati and four of his associates last month. Christian homes, orphanages and churches have been burned down, whilst 16 people have been killed. In one of the worst incidents, a young woman was burned alive when she tried to protect children from an attack on their Christian orphanage.

In a letter sent to the Most Rev Joel Dal, Moderator of North India, Dr Williams called for an end to the violence and urged Christians elsewhere to show their support for the Christian community in Orissa.

"I hope that Christians and people of faith around the world will make known their horror at this violence, their support for the rebuilding of lives and the churches, orphanages and schools destroyed, and for work towards future reconciliation," he said.

Christian leaders have appealed to the Indian Government to bring the perpetrators of the violence to justice and protect Christians in Orissa from further attacks. Persecution watchdog Barnabas Fund said the government's response appeared to be "patchy at best", with curfews only partially enforced. Whilst additional protection has been provided in the towns, this has not been the case in rural areas, the group said.

Rights groups estimate that around 16,000 Christians have fled the area, with many seeking shelter in makeshift government refugee camps. According to Reuters news agency, one temporary camp in Raikia village has 8,000 people crammed into two floors of a government office, where they are sleeping on the bare floor and surviving on a rice and lentil meal given twice daily.

Reuters said that the government camps were filled mainly with women and children, whilst their men folk continue to hide out in surrounding forests.

The All India Christian Council said Christians in New Delhi had gone on hunger strike on Tuesday to put pressure on the government to protect Christians in Orissa. Christian leaders and pastors are due to meet in the northern city of Chandigarh on Thursday to devise a "plan of action".

Orissa has a long history of violence between Hindus and Christians, fuelled particularly by the issue of conversions. The latest outbreak of violence follows a wave of Hindu attacks on Christians in Orissa last Christmas. Barnabas Fund said that many of the victims from the last attacks were still living in a refugee camp, awaiting the reconstruction of their homes.

The group has been assisting victims of the Christmas violence with food aid, clothes, replacement bedding, medical expenses, trauma counselling and school materials for children, and to help repair churches.

"Sadly these needs have once again become immediate and urgent," the group said.