Derek Beardsell, principal of Newbold College, the Seventh- day Adventist institute in Bracknell, Berkshire, said Koresh targeted British Adventists in a recruitment drive for his Branch Davidian cult because he thought the church would be 'fertile hunting ground'.
The 26 Britons thought to have been inside Koresh's headquarters in Waco, Texas, are believed to have been former Seventh-day Adventists. The original Branch Davidian sect broke away from the Seventh- day Adventist church in the 1920s. The church derived from 19th-century speculation about the imminent return of Christ to rule the earth with his saints for 1,000 years.
Mr Beardsell said: 'Seventh- day Adventists have an interest in the Second Coming. Koresh pretended to interpret the Book of Revelation and gave a picture that he knew what was going to happen, that he was the Messiah and that he would be able to tell what Armageddon was. He was specific, setting timetables.
'Some dismissed him but for others he gave the impression that he was above suspicion, more honest than honest. It was very difficult for them to drag themselves away from what he was saying. He had a terrific pull on the sensitive mind, on those who wanted a greater certainty. There are those who want something specific, to see things in black and white, and he provided it.'
On a recruitment visit to Britain in 1988 Koresh persuaded students to attend meetings in a private house near the college, where he lectured them for up to 17 hours. Hugh Dunton, a college tutor, said he presented himself as a messianic figure 'with the plan of salvation as a semi-divine figure, one who would eventually be killed for the good of mankind . . . He reminded me of Rasputin.'
Steve Schneider, Koresh's chief spokesman, studied at the college in the early Seventies but was expelled amid allegations of drunkenness. He returned to Britain in 1988, Mr Beardsell said, to lay the ground for Koresh's visit. Mr Schneider went on to Nottingham and Manchester, cities where the church is strong.
The beliefs of the mainstream Seventh-day Adventists can strike outsiders as bizarre. They abstain from pork, and observe Saturday, not Sunday, as the day of rest. But their interest in the imminent end of the world and the return of Jesus is common in fundamentalist Christianity.
The roots of Seventh-day Adventism lie in upstate New York. In 1831, a preacher named William Miller announced that after two years' deep study of the Bible, he could be certain that the end of the world would fall between 21 March 1843 and 21 March 1844.
This estimate had to be revised in due course, and a final, authoritative date of 22 October 1844 was set. The period after that is still known as The Great Disappointment.
Eventually, a few of Miller's followers came to realise that the prophesied 'cleansing of the temple' had in fact taken place, but in heaven rather than on earth.
Those who believed this came to be known as Seventh-day Adventists. Their dietary quirks sprang from an effort to purify their nature to make it more fitting for the wonderful end of the world. Kellogg's Corn Flakes were invented by an Adventist dietician.
Adventist leaders in Britain have stressed that the Waco group is not part of their organisation and that Koresh was 'disfellowshipped' in 1981. Last night Mr Beardsell said: 'The church was not surprised at the response after the FBI action. We are deeply saddened because of the number of former Adventists from Nottingham and Manchester involved. We have tremendous sympathy for the bereaved, many of whom are still members of the church.'