A man killed his girlfriend, then filleted and cooked parts of her body before calling police to tell them what he was doing, US authorities said.

Christopher Lee McCuin, 25, told police he had killed Jana Shearer, 21, and was boiling her body parts at his mother's home in Texas.

When police arrived at the home, they found Ms Shearer's mutilated body, one ear boiling in a pot of water on the stove and a fork sticking out of some human flesh sitting on a plate on the kitchen table.

Authorities said it was unclear whether McCuin consumed any part of Ms Shearer's body.

"We cannot prove that he did," Mr Smith said. "He was either going to, had been or led us to think that he was doing it."

Authorities believe Ms Shearer, 21, was abducted from her home on Friday night and killed.

Her death and mutilation was apparently the beginning of a crime spree that also included McCuin allegedly stabbing the boyfriend of his estranged wife and breaking into a business.

The stabbing victim is in a critical condition in hospital, officials said.

McCuin, from Tyler, about 110 miles east of Dallas, was charged with capital murder.

Before he called police, McCuin told his mother and her boyfriend to look in their garage.

There the couple saw the remains of Ms Shearer. McCuin's mother and her boyfriend fled the home and flagged down a police officer.