A man who allegedly confessed to killing seven women in Indiana refused to respond to the judge during his initial court appearance Wednesday, prompting her to postpone it and to warn him he'd spend "the rest of his life" in jail unless he cooperates.

When the judge asked Darren Vann, 43, if he swore to tell the truth at his initial court appearance in the strangulation death of 19-year-old Afrikka Hardy, he didn't respond or flinch and stood unmoving and stone-faced.

Lake Superior Court judge Kathleen Sullivan warned Vann, who stood with his wrists and legs shackled and flanked by two jail guards, he could be held in contempt and he still declined to speak.

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"Mr. Vann, are you choosing not to take part in this hearing?" Sullivan asked Vann during the hearing in a courtroom at the Lake County Jail in Crown Point.

Sullivan then addressed Vann's public defender, urging him to make his client speak.

"Tell your client that he stays in jail the rest of his life until this hearing takes place," she said.

Vann's public defender walked up to him and put his hand on Vann's shoulder encouraging him to speak, but he refused.

Sullivan said she would schedule another initial hearing for next week.

Vann, a convicted sex offender, is charged with the strangulation death of Hardy, whose body was found Friday in a bathtub at a Motel 6 in Hammond, 20 miles southeast of Chicago. Authorities said Hardy was involved in prostitution and had arranged to meet Vann at the motel through a Chicago-area website.

Police arrested him Saturday in Hardy's death after obtaining a search warrant for Vann's vehicle and home in nearby Gary. After his arrest, investigators say Vann directed them to the bodies of six other women in Gary whom he also confessed to killing. More charges are likely.

Officers found the body of 35-year-old Anith Jones, of Merrillville, Indiana, on Saturday night in an abandoned home. She had been missing since Oct. 8.

Five more bodies were found Sunday in other homes, said Hammond Police Chief John Doughty, who identified two of the women as Gary residents Teaira Batey, 28, and Kristine Williams, 36. Police have not determined the identities of the other three women, including two whose bodies were found on the same block where Jones' body was found Saturday.

Investigators in Indiana and Texas, where he has also lived and served prison time, have been poring over cold case files and missing person reports to determine if there are more victims.

Vann was convicted in 2009 of raping a woman in his Austin, Texas, apartment. He was released from prison last year and moved back to Indiana.

Before that conviction, he served a year in prison in Indiana after he grabbed a Gary woman in a chokehold in 2004, doused her with gasoline and threatened to set her on fire.

In both the Texas and Indiana cases, the charges against Vann were reduced in plea bargains, and Texas officials deemed him a low risk for violence. Vann registered as a sex offender in Indiana and police made a routine check in September that he lived at the address he provided.