Witness testimony began Monday in the case of Juan Rosario, accused of killing an 83-year-old woman back in 2013. 

Prosecutors says Rosario brutally beat Elena Ortega, robbed her, set her home on fire and left her to die inside.

The jury heard from Ortega's neighbors and from deputies and firefighters who found Ortega inside her home.

When Elena Wilson took the stand Monday, she talked about making sure that her elderly mother, who lived alone, was safe.

“I mean they never really had much, but she kept cash in two frames on her dresser. She put the cash in the back of the frame, thought it would be hard if someone came to..." she said, crying softly. "I’m sorry."

One of the most descriptive witnesses was a crime scene investigator, whose testimony appeared to support the state’s assertion of robbery as motive.

“Did you photograph that piece of furniture because of the open drawers?" asked Ryan Williams, who represents the state.

"Yes, sir," responded Joanna Fletcher. “Many of the items appeared to be open, cabinets and drawers. It appeared like it was ransacked at one point.”

After describing the crime scene, including a blood-soaked mattress by which Ortega was found, Fletcher noted that investigators uncovered an envelope with a substantial amount of cash. Fletcher said that investigators found the frames in which Ortega was known to hid money shattered in several pieces. 

The state says the case went unsolved for months because the community was afraid of Rosario.

But Rosario's attorney said the state's main witness, a woman who lived with Rosario at the time and said she helped him cover up the crime afterwards, is an unreliable witness who changed her story several times. 

"She is the whole state's case, and we are going to ask you to return a not guilty verdict for a lack of evidence," attorney Roger Weeden said in his opening statement to the jury. 

Weeden also brought up a man who helped Ortega with chores, attempting to show that Rosario may not be the only one capable of robbing Ortega.

The Rosario case is the first time Brad King, state attorney for the Fifth Judicial Circuit of Florida, will prosecute an Orange-Osceola Circuit Court case as special prosecutor to replace State Attorney Aramis Ayala.

Back in March, Ayala announced she would not seek the death penalty in any case and the governor reacted by taking her off 22 first-degree cases, including the Rosario case.

While a legal battle between Ayala and Gov. Rick Scott continues, King has agreed to try those 22 cases, announcing he would seek the death penalty in the one against Rosario.

The trial is expected to last throughout the week. And because this is a capital case, if jurors find Rosario guilty they will have to return for another week in May or June to decide if Rosario should be put to death or face life in prison.