Associated Press Writer

Wednesday, May 26, 1999; 4:49 p.m. EDT

THE HAGUE, Netherlands (AP) -- With speculation mounting that Slobodan Milosevic may soon be indicted, the tribunal charged with prosecuting war crimes in Yugoslavia said Wednesday it already is armed with evidence of atrocities ``on a massive scale.''

The U.N. court's chief prosecutor, Louise Arbour, said she would make ``an important announcement'' Thursday but would not comment on a CNN report citing unidentified European diplomatic sources as indicating an indictment against the Yugoslav leader was imminent. The tribunal never comments on indictments before announcing them.

However, a diplomatic source at NATO headquarters in Brussels, Belgium, told The Associated Press that an indictment of Milosevic appeared to have been in the works for several weeks. ``It's another way of squeezing him and actively trying to stop him,'' said the source, speaking on condition of anonymity.

In fact, Milosevic may well already have been placed under secret indictment, a tactic the Yugoslav war crimes tribunal to issue indictments ``regardless of their position within the Serbian leadership.''

In doing so, the court would be bringing charges on the basis of so-called ``command responsibility'' -- the failure of leaders to prevent or punish war crimes carried out by subordinates.

Sen. Arlen Specter, R-Pa., who has long advocated that Milosevic be indicted, said on the Senate floor Wednesday that such an action would be ``good news. It shows the war crimes tribunal means business.''

Specter said ``there is an abundance of evidence of atrocities and mass murders'' in Kosovo that can be tied directly to Milosevic. ``Those crimes should not go unpunished.''

Separately, 63 members of the House urged the Clinton administration to make Milosevic's indictment for war crimes a top priority, and urged the administration to provide the tribunal with all information it has that could lead to an indictment.

Arbour's spokesman, Paul Risley, told a weekly briefing in The Hague on Wednesday that the court's investigators already had amassed ``evidence of war crimes on a massive scale.''

``The challenge is not to receive the information but to determine which areas to focus on, to zero in on,'' Risley said. He would Canadian Supreme Court, saying only that she would consider such an offer if one is made.