WICHITA, Kan. — As the murder trial continues for the man charged with gunning down abortion provider George Tiller, the drama isn't limited to the courtroom.

Supporters of Scott Roeder continued to arrive in Wichita on Tuesday, and abortion-rights advocates called on federal authorities to step up their investigation into a possible conspiracy of anti-abortion violence.

The Roeder supporters themselves, and their statements this week, are evidence enough that there's an extremist network said, said Kathy Spillar, executive vice president of the Feminist Majority Foundation, who is attending the trial.

"Many of this extremist network with whom Scott Roeder clearly has been involved are here in the courtroom," Spillar said. "We can only hope that the network will be dismantled, and until it's dismantled, we're waiting for the next murder."

Those attending Roeder's trial say they pose no threat to anyone.

"This is another waste of taxpayer dollars," said Michael Bray, of Ohio, who spent four years in prison in the 1980s for a series of abortion clinic arsons and bombings.

Roeder, 51, of Kansas City, is charged with first-degree murder in the death of Tiller, who was shot May 31 while ushering in his church.

Roeder has admitted to reporters and in a court filing that he killed Tiller, saying it was necessary to save unborn babies, but he has pled not guilty.

On Tuesday, the third day of testimony in the trial, the prosecution traced Roeder's actions, showing video of him purchasing a gun and being arrested after the shooting.

Among Roeder's supporters attending besides Bray are Dave Leach, of Des Moines, who once published the Army of God manual, a how-to book on abortion clinic violence; Jennifer McCoy of Wichita, who spent time in prison for two abortion clinic arsons in Virginia; Regina Dinwiddie of Kansas City, who calls Roeder a hero; and Joshua Graff, who spent three years in prison for a 1993 clinic arson in the Houston area.

After Tiller was killed, the U.S. Department of Justice announced that it had begun an investigation into whether others were involved in the shooting. Justice Department officials say the investigation is continuing.

"Our investigation remains open and ongoing," said Justice Department spokesman Alejandro Miyar on Tuesday. He added, however, "I decline further comment, as we do not discuss open investigations."

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