Updated

An internal debate over the targets of Cambodia's Khmer Rouge genocide tribunal turned into a public dispute Wednesday, when judges ordered a prosecutor to retract his call for further investigations.

The fight at the United Nations-backed tribunal added to mounting fears that prosecutions are being quashed for political reasons.

The two investigating judges, from Germany and Cambodia, on Wednesday ordered British co-prosecutor Andrew Cayley to withdraw a statement he issued last week citing specific crimes that deserved further investigation. They said the statement violated tribunal rules and must be retracted within three days, without specifying the punishment for failure to comply.

Critics fear the judges ended their investigations prematurely into what the court calls Case 003, bowing to Prime Minister Hun Sen's demands that the trial's focus be kept narrowly on the one suspect convicted last year and four set for trial next month.

About 1.7 million people died of starvation, exhaustion, lack of medical care or torture during the communist Khmer Rouge's reign of terror in the 1970s.

Cayley's statement was issued just a few days after co-investigating judges Siegfried Blunk and You Bunleng announced that all investigations into Case 003 had been concluded.

The tribunal follows French-style law, which mandates that investigating judges collect evidence that is then forwarded to prosecutors who decide whether to go to trial. There are parallel sets of Cambodian and international judges and prosecutors working together.

Legal observers and victims advocates complained that the investigations into the new cases were cut short without even the most basic effort being made, such as summoning the suspects for questioning.

"They've basically done a desk study, and it appears that that desk study was a sham," Brad Adams, Asia director for Human Rights Watch, said in an interview last week in Bangkok. "It was a political decision, it appears, to shut down this case."

Cayley's statement called the investigation inadequate and detailed previously unreleased information about the yet-to-be-prosecuted cases, including information about mass graves and other alleged crime sites.

The judges' order said that Cayley violated court confidentiality rules and ordered him to publicly retract his statement within three days.

Cayley was traveling and could not be reached for comment Wednesday. But his deputy, Bill Smith, told The Associated Press that Cayley had not decided yet whether to appeal the judges' order. He said Cayley was justified in releasing the information under court rules.