A federal judge indicted two U.S. pilots and four Brazilian air traffic controllers on manslaughter-related charges Friday in Brazil's worst air disaster, court officials said.

Judge Murilo Mendes accepted the charges filed by a prosecutor last week in a federal court in Sinop, a small city near the Amazon jungle site where a Boeing jetliner last year plunged into the rain forest after a collision with an executive jet. All 154 people aboard the jetliner died, while the executive jet landed safely.

"Now the criminal process begins," court spokesman Fabio Paz said by telephone.

The American pilots have been called on to give preliminary depositions on Aug. 27 and the flight controllers have been called to testify a day later, said Paz.

Pilots Joseph Lepore, 42, of Bay Shore, N.Y., and Jan Paladino, 34, of Westhampton Beach, N.Y., were charged with exposing an aircraft to danger resulting in death. Paz said the charge is similar to involuntary manslaughter and is punishable by one to three years in prison.

A lawyer for the pilots said the charges were unfounded.

"The pilots' conduct was completely competent throughout the flight and cannot be fairly characterized as criminal," said Joel R. Weiss. "The allegations against the pilots are inaccurate, and the pilots are innocent."

He added: "The fact is that air traffic control placed and approved these two aircraft on a collision course, on the same airway, and altitude traveling toward each other. That is the overwhelming, obvious root cause of this accident."

The men were detained for two months after the crash. They were allowed to return to the Long Island, N.Y., communities late last year after signing a document promising to return to Brazil for their trial or when required by local authorities.

Neither pilot could be immediately reached Friday. A call to a phone number listed under Lepore's name went unanswered and Paladino's number was unlisted.

Though the Brazilian judge wants the pilots questioned in Brazil, lawyers for Lepore and Paladino previously suggested that could happen in the United States. They have declined to speculate on whether the pilots would return to Brazil.

Lepore and Paladino were flying an Embraer Legacy 600 executive jet when it collided on Sept. 29, 2006, with a Boeing 737 operated by Gol Linhas Aereas Inteligentes SA, sending the passenger jet crashing into a remote swathe of the jungle.

One of the four controllers was indicted with the more serious crime of knowingly exposing an aircraft to danger — similar to manslaughter — while the others face the same charges as the pilots.

Mendes in his ruling accepted the prosecutors' arguments that the air traffic controllers could be tried in civilian courts. Before the prosecutor asked for the indictments, Brazilian officials consistently said the military controllers could only be charged in military courts.

Under Brazilian law, judges — not grand juries — issue indictments.

The two pilots were detained for two months after the crash. They were allowed to leave the country after promising to return for any court proceedings.