The collapse of a church building in eastern Nepal's Sunsari district today killed at least 24 people, including an Indian, and injured 63 others, the police said.

The people had gathered in Dharan, some 400 kilometres southeast of the capital, yesterday for a week-long Christian conference, and many chose to sleep on top of a church extension made of bamboo and tin roofing, the police said.

The convention was organised by the El-Shaddai Church, an international Christian organisation with a base in the northern Indian town of Darjeeling.

"The participants were preparing to sleep when the wall collapsed. Most of the victims were on the ground floor of the building," the police said.

Among the 24 killed were 17 women and four children, officials said. The 63 people injured were taken to the nearby B.P. Koirala medical college hospital, according to the national news agency RSS.

One of the dead has been identified as 35-year-old Neeru Rai from India. Some Indian nationals may be among the injured as there were many participants from India, the police said. However, no details about the identity of the injured were available.

Thirty-two people have been discharged from the hospital after receiving treatment while the rest were under treatment, according to Manjil Moktan, a policeman. He said the police were still probing the incident.

Some 1,500 Christians had gathered in Dharan from across the country and neigbouring India, for the conference, which coincides with the Dashain festival.

The army has been drafted to assist the local administration in the rescue effort, officials said.

The Prime Minister Madhav Kumar Nepal condoled the death of the Christians in the church collapse. He said he was shocked by the incident and expressed his condolence.