Members of a drug trafficking ring accused of at least 13 cult slayings gave investigators details Friday of their Caribbean religion and told authorities they were forced to repeatedly watch a 1987 horror movie that featured the bizarre beliefs they practiced.

FBI agent Bob Nixon of Brownsville said his agency filed charges of interstate flight to avoid prosecution to add federal clout to the two-country search for the alleged ringleaders of the cult: Adolfo De Jesus Constanzo, 26, and Sara Aldrete, 24."They could kill for any reason. They are very dangerous," Lt. George Gavito, chief investigator for the Cameron County sheriff's office, said of the two people charged in Texas with federal narcotics trafficking and aggravated kidnapping in the abduction of one of the two U.S. victims of the cult, whose victims included at least 13 men and boys.

Authorities received several reports of sightings of the pair from across the country Friday but were unable to confirm any of them.

U.S. authorities who Friday spent three hours interviewing the four suspects being held at a Mexican jail said the suspects told them they practiced Palo Mayombe, the offshoot of Santeria depicted in the movie "The Believers."

The couple began practicing Santeria, an African-influenced Caribbean religion that includes animal sacrifice, about 14 months ago, Gavito said. They switched to Palo Mayombe, which uses human bones, nine months ago, about the time the recruitment began.

Palo Mayombe flourished in parts of Florida and Louisiana after the Cuban influx of the early 1980s, but followers stole the human bones used in rituals from graveyards, said Rafael Martinez, a Miami folk religion expert.

"This is the first time I've heard of live victims sacrificed," he said.

"The Believers," which starred Martin Sheen, was the story of a widower who moves to New York City and becomes involved with a form of Santeria linked to serial killings.

Suspect Elio Hernandez Rivera, 22, told investigators he became a priest with the authority to kill after Constanzo used a knife to cut crosses and arrows into his chest, back and arms, Gavito said.

"Elio is the priest. The Cuban (Constanzo) is the (leader of the group). Everybody else was a member," he said. Aldrete was used for recruitment.

"Sara's the one who brought everyone in," Gavito said.

Aldrete made new recruits watch videotapes of the movie repeatedly, Gavito said.

"They were told to watch it, and they watched it a lot of times," he said.

Neck said, "It's going to take weeks or months to unravel (the case). The key to the whole thing is these two subjects - El Padrino and the lady. When we have those two, we can unravel a lot more."

Mexican and U.S. authorities Friday said they hoped insurance problems would be resolved quickly so donated heavy digging equipment could be taken across the border to the ranch Saturday for an extensive search for more bodies.