The Home Secretary Theresa May is being urged to step in to prevent a Nigerian “witch hunter” returning to the UK after she flew in to preach to congregations in London.

“Lady Apostle” Helen Ukpabio, founder of the controversial Liberty Foundation Gospel Ministries, is believed to still be in the capital after addressing three gatherings last week.

The born-again Christian Pentecostal preacher claims to have been betrothed to Satan as a teenager before being rescued from a cult at the age of 17. She now specialises in liberating captives in “deliverance sessions” that critics claim are little more than crude exorcisms.

Among her advice to parents is the suggestion: “If a child under the age of two screams in the night, cries and is always feverish with deteriorating health, he or she is a servant of Satan.”

Campaigners say such beliefs, prevalent in some parts of the developing world, can put children’s safety at risk. They have written to Ms May to urge that the pastor be banned from the UK after the current tour.