LOS ANGELES (AP) _ The judge in the trial of three reputed gang members accused of killing Oscar-winning actor Haing Ngor imposed a news ``blackout'' Monday, then banned reporters from his courtroom when they refused to comply with his order to withhold information.

Ngor, 55, a Cambodian activist who won an Oscar for his role in ``The Killing Fields,'' was shot to death during a robbery near his home in February 1996.

Superior Court Judge J.D. Smith said the blackout was necessary because each of the defendants has a separate jury and he wants to shield members of the individual juries from hearing about evidence that may never come before them.

His ban on press coverage came moments before prosecutor Craig Hum was to begin delivering three separate opening statements to the juries. Smith asked reporters if they would agree not to report on the first two opening statements.

The Associated Press told the judge it could not agree to withhold information.

``In that case, all press is out of the courtroom,'' the judge declared.

A handful of reporters in court left and opening statements proceeded. Spectators were allowed to remain.

Later, reporters were allowed to return for the third opening statement.

The judge said his concern was prompted by statements to police made by some of the defendants that may implicate their co-defendants. Smith is seeking to protect jurors from that information if it does not apply to their defendant and has forbidden members of each jury from talking to members of the other two juries.

The contents of tape-recorded interviews with the defendants could be played or discussed during opening statements. However, the judge said he had no idea if Hum planned to refer to the statements at the time he ousted the press.

Attorney Kelli Sager, representing the AP and other news organizations, appeared in court and sought a hearing on the ouster of the reporters but the judge refused to hear arguments. He also declined to put his order in writing.

Ms. Sager said she would seek immediate appellate review of the issue.

There was early speculation Ngor was killed for political reasons, but police eventually arrested three young, alleged gang members and said they killed him during a street robbery.

Attorneys for the defendants say police arrested the wrong people.

Tak Sun Tan, 21; Indra Lim, 20, and Jason Chan, 20, were ordered to stand trial together, but the case became complicated when they gave separate statements to police. Their lawyers asked for three trials. The judge, trying to streamline the process, ordered three juries instead.

The procedure, which has been used only once before in California, has produced a crowded courtroom and a group of jurors who are color coded and must be shuttled in and out of court when matters are heard that don't concern their defendant.

The judge indicated he would place additional restraints on the press when there is testimony about the defendants' statements to police.