The "phenomenon" has landed to bring relief to the dispossessed of Haiti. John Travolta was in the pilot's seat of his Boeing 707 flying in doctors, medical supplies, ready-to-eat military rations – and Scientology ministers.

Travolta's visit – which the star called Operation Phenomenon – is not the first Scientologist trip to Haiti since the shattering earthquake a fortnight ago: there are already 150 members in Haiti, as well as 250 medical staff. Soon the group hopes to have 400 of each in place.

"Our volunteers are coming from all over," said Frank Suarez, one of dozens of yellow T-shirt-wearing members who have set up a camp at a gym in the capital, Port-au-Prince. "The need is huge."

Whatever the intentions of the volunteers, Travolta's trip has reignited controversy over the management of supplies into the airport, and Scientology's broader aims in Haiti.

Critics point out that while the actor was able to fly in 7,000lb of medical supplies, aid groups have been forced to wait because of congestion. Médecins Sans Frontières say the priorities decided by US military controllers have led to deaths. At least 800 relief planes are currently on the waiting list.

But Travolta was adamant about the trip yesterday. With his actress wife, Kelly Preston, at his side, he said: "We have the ability to actually make a difference in Haiti, and I just can't see not using this plane to help."

On the ground in Port-au-Prince, the situation remained desperate. Hours before Travolta's flying visit, a mini riot broke out in front of the collapsed presidential palace where food was being distributed.

The jostling 4,000-strong crowd took no notice of the 18 Uruguayan UN peacekeepers waving pepper spray under their noses or firing rubber bullets into the air. Asked why they were not trying to calm people by talking to them, one soldier cried: "Whatever we do, it doesn't matter – they are animals."

Medicine was not in much greater supply than food. But a group of Scientologists working in the hospital courtyard shrugged off the shortages, saying they were healing patients through "the power of touch to reconnect nervous systems". Sylvie, a French woman, said: "We are trained as volunteer ministers, we use a process called 'assist' to follow the nervous system to reconnect the main points."

One 22-year-old whose leg had been amputated, Oscar Elweels, received the touch treatment on his remaining damaged leg. What did he know about Scientology? It was, he responded, a French charity.

Doctors were sceptical. "I didn't know touching could heal gangrene," one said. L Ron Hubbard, founder of the group, once wrote about a technique called "casualty contact", which sought to exploit disasters as recruiting opportunities, but warned his followers against portraying them as such to outsiders.

The Scientology spokeswoman Linda Hight said yesterday that such an attitude was unduly cynical. "They're definitely not there to talk about Scientology," she said. "The volunteer ministers have tremendous organisational skills, they haul water, they build latrines."

'Casualty Contact': The Hubbard method

L Ron Hubbard, the founder of Scientology, said the following about recruiting followers in times of tragedy:

"Every day in the daily papers one discovers people who have been victimised... [The Scientologist] should enter the presence of the person and give a nominal assist, leave his card which says where church services are held with the statement that a much fuller recovery is possible by coming to free services... Handling the press he should simply say that it is a mission of the church to assist those in need."

February, 1956

"Casualty contact is very old, is almost never tried and is almost always roaringly successful... This is a pretty routine drill really. You get permission to visit. You go in and give patients a cheery smile. You want to know if you can do anything for them, you give them a card and tell them to come around to your group... Your statement, 'the modern scientific church can cure things like that. Come around and see' will work. It's straight recruiting!"