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A 19-year-old Texas A&M University student was killed by her ex-boyfriend, who then dismembered and burned her body on a patio grill, authorities said Saturday.

Investigators say Timothy Wayne Shepherd, 27, confessed Wednesday to strangling Tynesha Stewart because he was angry she had begun a new relationship. Shepherd, who is charged with murder, is being held on $250,000 bond.

"We have determined through this investigation that the defendant dismembered Tynesha Stewart and . . . he burned the body parts," Harris County Sheriff Tommy Thomas said. "There are no remaining body parts."

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The announcement was the latest in a debate that has raged since Thursday in the Houston area, when authorities said they would not search for Stewart's body because there was little chance of success.

Officials first thought that the body had been disposed in a large commercial trash bin that had since been emptied. Authorities believed her remains were scattered in several overflowing landfills, and that the search would be expensive and nearly impossible.

The decision angered family and friends, and complaints from activists and lawmakers prompted Thomas to get emergency approval to spend up to $500,000 for a search. But the search never began.

Thomas said he knew, but could not disclose, that there were no body parts to find. He said investigators were unable to release that information to the public or to Stewart's family because of the investigation. Stewart's family has since been advised, and understands why there will be no search, Thomas said.

Stewart, a college freshman from Houston, was last seen with Shepherd on March 15 while she was home for spring break visiting her mother. Friends have said Stewart and Shepherd quit dating at the beginning of this school year.

Shepherd's attorney, Chip Lewis, has not returned calls for comment. A call seeking comment was made to Stewart's mother Saturday night, but there was no way to leave a message. Thomas said the family had asked for privacy and would not respond to media calls.

Authorities did not give any more details about how they believe the slaying occurred, but said nothing remains of Stewart. Although human remains generally require extremely high temperatures to destroy, Thomas would not discuss how he believed the body could be burned to nothing.

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