New York real estate heir Robert Durst (searchtestified Tuesday that when he cut up his neighbor's body, it was like "a nightmare with blood everywhere."

Durst, accused of murdering 71-year-old Morris Black (search), had said a day earlier he did not recall details about the dismemberment. But when pressed by prosecutor Joel Bennett on Tuesday, he said he remembered the blood.

"It was like waking up from a dream or a nightmare with blood everywhere," Durst said. "I remember like I was looking down on something and I was swimming in blood and I kept spitting up and spitting up and I don't know what is real and I don't know what is not real."

During his fourth day of testimony, Durst said he then cleaned his apartment with a mixture of water and cleanser.

Prosecutors suggested as the questioning wrapped up that Durst killed Black to steal his identity.

"You became Morris Black after he was dumped in the bay," Bennett asked Durst. "You impersonated Morris Black, didn't you?"

Durst said the accusation wasn't true, but said he used Black's driver's license and Medicare card to rent cars in Mobile, Ala., and New Orleans after disposing of his neighbor's remains.

Durst said he wanted to make it appear as if Black had moved, but wasn't trying to steal his identity.

The cross-dressing millionaire claims that Black died accidentally during a struggle over a gun and that he cut him up with two saws and an ax and disposed of the body in Galveston Bay because he feared authorities would not believe him. Prosecutors contend that Durst intentionally shot Black and that everything he did after that showed his guilt.

Durst, 60, whose family runs The Durst Organization (search), a privately held $1 billion New York company, faces from five to 99 years in prison if convicted.