HOUSTON » A blue suede stiletto heel that prosecutors say a Houston woman used to fatally stab her boyfriend at least 25 times in the face and head was shown at her trial Tuesday.

The shoe — a size 9 platform pump with a 5 1/2 -inch heel — was brought out during testimony about the bloody crime scene at the trial of Ana Trujillo, who’s accused of killing 59-year-old Alf Stefan Andersson. He was a University of Houston professor and researcher. A prosecutor later stood on top of a table in the courtroom and straddled a dummy to demonstrate for jurors how authorities believe the shoe was used as a weapon.

Authorities allege Trujillo sat on top of Andersson and struck him with the shoe during an argument at his condominium last June. Trujillo’s attorney has told jurors his client was defending herself.

Also Tuesday, prosecutors played the 911 call Trujillo made in the early-morning hours and showed jurors video of the crime scene, where the shoe could be seen near Andersson’s body.

On the call, Trujillo could be heard at times crying uncontrollably, telling the operator her boyfriend had "started beating me up." She also told the operator that Andersson is "bleeding, he’s about to die."

It was difficult to understand Trujillo, and the 911 operator seemed to be unsure if Trujillo was reporting an assault or that someone was injured and needed medical help.

When the operator realized someone needed medical attention, she transferred the call to emergency medical services, which directed Trujillo to perform CPR on Andersson. Trujillo said she was already doing that.

Trujillo, 45, cried in court as the 911 call was played.

Houston police officer Ashton Bowie testified that when he responded to the condominium, Trujillo was "covered in blood." Bowie said that he found Andersson lying on the ground, face up. His face was covered in blood and swollen.

"I thought his head had been blown out by a gun," he told jurors.

Bowie also said he questioned Trujillo’s emotional response to the slaying.

"She was sobbing but no actual tears were coming down her face," he said.

In video taken by police at the crime scene, the stiletto heel can be seen lying on the carpeted floor of Andersson’s condominium, above his head. A large pool of blood was also near his head, which was bloodied, purple and had several visible wounds.

Prosecutor John Jordan showed the shoe to jurors after the video.

Later Tuesday during testimony from Houston police officer Chris Duncan, with the crime scene unit, Jordan grabbed the shoe and pretended to strike the dummy with it.

Duncan had earlier testified that blood spatter he found on walls near Andersson’s body was created by someone hitting Andersson while he lay on the ground.

"Is all of it consistent with him being struck by this high heel shoe?" Jordan asked.

"Yes sir," Duncan said.

Trujillo’s attorney, John Carroll, suggested to jurors that the blood spatter could have been caused by Trujillo slapping Andersson as she tried to revive him.

Carroll also suggested defensive wounds Duncan testified Andersson sustained on his hands as he was trying to block blows might have actually been wounds he got when Trujillo was defending herself.

Testimony was to resume Wednesday.

The trial is expected to last at least a week. If convicted, Trujillo faces up to life in prison.