Angie

Speaking to the BBC, Angie said she shared a dormitory with Marten while the pair were at the church.

In October 2012, she got in touch with Angie via Facebook Messenger.

She said it would be a great help "both emotionally and spiritually" to talk to Angie, who replied and later met Marten twice.

For Angie it has been difficult to watch how events have unfolded for her former friend.

Marten's first job after leaving university was as a researcher at the Al Jazeera news channel, where she tried to make a documentary about TB Joshua's megachurch - a project she mentioned in messages sent to Angie in early 2013.