Hours after two police officers were shot at a protest in Ferguson, Missouri, last week, a black Kenworth truck in North Carolina hauling a collapsible conference room began rolling down the highway toward the scene, intent on bringing peace and saving souls.

The truck, one of Christian evangelist Billy Graham's Rapid Response Team vehicles, sped toward the latest U.S. crisis armed with chaplains trained to help people cope with everything from tornadoes to mass shootings.

"The police force needed chaplains after the shooting, and we've also been serving the protesters," said Al New, manager of the team's U.S. deployments, who drove the truck.

Ferguson, reeling since the shooting death of 18-year-old Michael Brown seven months ago and subsequent demonstrations, has been thrust into the center of a national debate on race and policing.

Tensions flared this month with the release of a U.S. Justice Department report detailing what it called systemic bias in the police force and a court system that disproportionately levied steep fines on Ferguson's black residents.

On Sunday, when officials announced a suspect had been arrested in the shooting of the police officers, shouting and shoving broke out among scores of protesters outside Ferguson's police station.

Soon, uniformed Graham chaplains emerged from the mobile conference room parked across the street, talking people down and even dragging a woman by the wrist from an angry crowd.

Over the course of the day, the chaplains invited people into the truck, offering snacks and prayer.

Graham, now 96, became one of America's best known Christian television and radio evangelists in the 1950s and 60s, serving as spiritual adviser to presidents from Dwight Eisenhower to Richard Nixon, and supporting Martin Luther King's civil rights campaign.

With son Franklin now in charge, the Billy Graham Evangelistic Association operates a variety of programs such as the Rapid Response Team.

The program, set up after the Sept. 11, 2001, attacks, has 1,800 volunteer chaplains in the United States and has chalked up more than 250 deployments, from tornadoes and hurricanes to shootings.

New, a former firefighter from Tennessee, said the donor-funded Rapid Response Team first visited Ferguson in November, after a grand jury cleared a white police officer of wrongdoing in Brown's death, touching off street violence.

Chaplains, he said, soon found themselves at the mercy of the city's most feared drugs gangs.

"Two gang members came and told us to leave," New said. But after talking, the neighborhood's female gang leader, nicknamed 'The Queen,' decided to let them stay.

"From then, the gangs were our protectors," New said.

He said three gang members gave up their guns and another 100 area people "gave themselves to Jesus."