Police were able to obtain a warrant to search a missing Illinois woman's home last week because they had found traces of her blood on a tarp in her husband's vehicle, the Naperville Sun reports.

Lisa Stebic's blood was found in her husband's vehicle and provided as evidence to obtain a search warrant, executed on the couple's Plainfield, Ill., home on the evening of May 14, according to an unnamed police source.

Click here to read the Naperville Sun's story.

Officials used the blood evidence to obtain the warrant by positing a scenario that Craig, an avid hunter, might have used the tarp to transport his wife's body from the home, the source told the newspaper.

Charles Pelkie, spokesman for Will County State's Attorney James Glasgow, would neither confirm nor deny the report for the Sun, saying that "the contents of the warrant are under court seal."

But FOX News confirmed that the car the blood was found in was one of the family's two vehicles, a 2002 Chevrolet S-10 pickup truck. The family's other car was a 2004 four-door Saturn Ion. Both were registered to Craig Stebic, but Lisa used the Saturn. Both have been confiscated by police.

On Saturday, friends and family of Lisa Stebic gathered for a candlelight vigil to mark the mother of two's 38th birthday.

"It's difficult to be optimistic this many days out," family spokeswoman Melanie Greenberg told the Sun. "But we can never completely lose hope."

Stebic was last seen at about 6 p.m. April 30 at her Red Star Drive home in Plainfield, Ill.

She disappeared while her husband — from whom she was seeking a divorce — was in the backyard and her two children were out. Since then, there has been no activity on her cell phone or credit cards.

The search on May 14 was the first time authorities publicly acknowledged Stebic may be a victim of foul play.

"We need to focus part of our investigation on the fact that she may not have voluntarily disappeared," Plainfield Police Chief Don Bennett told the Sun.

Craig Stebic has never been named a formal suspect in the case and has been compliant with police requests, according to Michelle Sigona, a correspondent for America's Most Wanted, which has profiled the Stebics' case. Craig Stebic gave police the family's computer but would not submit to a lie-detector test on the advice of his attorney, Sigona told FOX News.

It was reported May 17 that Stebic was trying to have her husband evicted from their Plainfield, Ill., home so the family could "live in peace."

Stebic's petition for temporary eviction stated he was being "unnecessarily relentless, cruel, inconsiderate, domineering and verbally abusive," reported the Sun. His behavior was "jeopardizing the mental well-being" of their children, she wrote.

Divorce proceedings began in December. The couple has lived in the same house since then but rarely spoke.

Craig Stebic's attorney, Dion Davi, denied the abuse allegations to the Chicago Tribune, noting the couple cited irreconcilable differences in their divorce action. He said Stebic was never in danger from her husband.