The supreme leader of the Exclusive Brethren church has flown in to New Zealand on a private jet, sources say.

Bruce Hales, also known as the Elect Vessel and Man of God, has wide-ranging powers over the 40,000 worldwide members of the Exclusive Brethren, 8,000 of whom live in New Zealand.

A current church member said Hales, a reclusive multi-millionaire from Sydney, was visiting because he was unhappy with his New Zealand followers. He had raised concerns about "lawless and wicked" behaviour.

STACY SQUIRES/STUFF At least 15 white busses were lined up inside the gates, as well more than 20 white vans.

The member asked not to be identified for fear of being labelled a traitor and thrown out of the church for speaking to media.

READ MORE:

* Exclusive Brethren told to pray for Bill English

* Hales tells tells followers to drink rat poison

* Hansen, Apiata preach teamwork to Exclusive Brethrens

It's understood Brethren congregations in New Zealand have also been told to repent for their excessive consumption of alcohol.

STACY SQUIRES/STUFF Security guards keep watch outside an Exclusive Brethren conference in Christchurch.

A church spokesman, Doug Watt, denied that was the reason for Hales trip to New Zealand.

"We hold regular Bible study sessions for encouragement, pastoral care and spiritual growth for the community," he said.

"We've been enjoying encouraging Bible readings together in Christchurch for a few days and also have meetings in Rangiora."

STACY SQUIRES/STUFF A neighbour said conferences were common, but never this big.

Watt said about 1000 church members attended the Bible conference in Christchurch.

Alcohol is a familiar feature of life in the Exclusive Brethren, whose members call themselves the Plymouth Brethren Christian Church.

Former members have described how mantras were recited in the church such as "drink makes a strong man stronger, and a weak man weaker".

Security was tight as church members descended on their Tuckers Rd stronghold in Christchurch ahead of a visit from Hales on Friday.

A white-shirted church member at the gate, Eddy Suckling, said it was "just a church conference".

"There are a few from around the regions that have come in, just locals," he said.

Suckling was unable to say how many people were inside, but cars were forced to park on the grass surrounding the 200-plus car park alongside the hall.

At least 15 white buses were lined up, as well as more than 20 white vans. Shiny white SUVs and utes filled the adjacent streets.

One neighbour, who did not want to be named, said conferences were common, "but nothing as big as this".

"It would have been nice if they had told us it was happening, we don't have anywhere to park now," she said.

"They're usually this big when one of the big wigs is in town, probably from America or Australia."

Suckling, who had travelled from Masterton for the conference, said he was unaware of anyone from overseas coming to the event. "I'm just helping out with traffic and organising the cars," he said, before a voice came through his earpiece and he was called away.

On Friday evening, a full black tinted Range Rover pulled out of a Christchurch address where Hales was believed to be staying, followed by a security team in a separate car.

Hales has previously used a Bombardier CL-600 Twin Jet Challenger to travel to church conferences.

Church spokesman Watt said the Church regularly organises fellowship meetings for so church members can get together to "learn more about the Bible and enjoy each other's company".

"We have a lot of younger members who enjoy getting together at these fellowship occasions to meet up with their friends and participate in the meeting," he said.