Prosecutors have filed felony jury tampering charges against the brother-in-law of a Southern California man who was sentenced to death earlier this year for setting a wildfire that killed five federal firefighters, authorities said Wednesday.

Christopher Vaughn Hillman, 46, was charged Aug. 7 with seven counts of jury tampering for allegedly placing copies of newspaper articles about banned evidence on the windshields of jurors during the trial of his brother-in-law, Raymond Lee Oyler.

Hillman fled his home during the execution of a search warrant more than two weeks ago and has been a fugitive ever since, Riverside County District Attorney Rod Pacheco said. Pacheco delayed announcing the charges until Wednesday because investigators had hoped to negotiate with family members for Hillman's surrender.

Oyler was sentenced to death June 5 after a Riverside County jury convicted him of five counts of first-degree murder, 20 counts of arson and 17 counts of using an incendiary device to commit arson.

Oyler set the Esperanza Fire days before Halloween in 2006 near Cabazon, about 90 miles east of Los Angeles. The flames were pushed by hot, dry winds and quickly charred 70 square miles of terrain and destroyed 34 houses and 20 outbuildings.

The crew of U.S. Forest Service Engine 57 was overrun by flames while defending an isolated hilltop home in Twin Pines. Witnesses testified during the trial that footprints and a trail of dropped gear at the scene indicate that at least one firefighter tried to run from the flames and fled for about 30 seconds before he was overcome.

Deputy District Attorney Michael Hestrin told jurors that in their final minutes, the firefighters faced flames that were 70 feet high, winds up to 40 mph and temperatures that reached 1,300 degrees.

Pacheco said Wednesday that Hillman placed copies of newspaper articles about an alternative arson suspect on juror windshields around Feb. 26, about halfway through the trial. Three jurors discovered the articles during a lunch break and sheriff's deputies found copies on four other jurors' windshields, the district attorney's office said.

Riverside County Superior Court Judge W. Charles Morgan called panelists into his chambers individually to question them about the fliers. He allowed the trial to continue and did not remove any jurors.

Pacheco said the transcripts of those interviews are sealed.

Mark McDonald, Oyler's defense attorney, said the articles were about a U.S. Forest Service arson investigator who was suspected of setting blazes in the same area in 2006. At the time, the investigator was jailed in Los Angeles on arson and criminal threat charges unrelated to Oyler's case. The judge ultimately rejected McDonald's bid to introduce him as an alternative suspect after a lengthy pretrial hearing.

McDonald said he was furious that someone would try to tamper with the jury and thought it hurt Oyler's case.

"I thought it gave a black eye to the defense, it made us look sleazy," he said. "Whatever he thought he was doing to try to help, all he did was cause more problems."

Authorities found Hillman's fingerprints on the fliers, Pacheco said, and during a search of his home found more copies of the fliers and other evidence.

"It was an extreme crime in extreme circumstances and we'll pursue this guy until we get him," Pacheco said.