Maria Kukucova murder trial
Andrew Bush and the woman charged with killing him, Maria Kukucova, in happier times. YouTube

In a dramatic day on the witness stand, sobbing former swimsuit model Maria Kukucova told how she accidentally shot her millionaire British boyfriend three times as they struggled for control of a pistol he was brandishing.

"I didn't want to cause him any harm," said the 26-year-old Slovakian model in a Spanish court, where she is on trial for killing British jewelry magnate Andrew Bush, 48, in 2014. "The gun just went off. I just wanted to break free from his grasp."

She said she wasn't clear on the two following shots after the first blast deafened her, the Telegraph reported.

Prosecutors charge that Kukucova lay in wait with a gun for Bush to enter his holiday home in Costa del Sol, then shot him twice in the head and once in the arm. She then placed the gun in Bush's hand as he lay in a pool of blood, they argue.

Kukucova said she had spent two days in Bush's mansion collecting her things because the couple had split up in late 2013. She said she expected to have the place to herself, but Bush suddenly drove up with his new 20-year-old girlfriend.

Bush began shouting at Kukucova, and gripped her by the arms and neck and threatened to kill her and her family before going to lock the door to the house and returning to point a gun at her, she testified.

Bush had told the new girlfriend, Maria Korotaeva, to wait outside in the car. Korotaeva said she heard the shots, then saw Kukucova race out and drive away. Kukucova finally gave herself up when she got to Slovakia.

Kukucova had worked for Bush in a jewelry store he owned in the UK before he moved to Spain. The two broke up about a month before the killing after a relationship of more than two years.

Kukucova's trial, held in Malaga, Spain, is expected to last two more days. Prosecutors are seeking a 20-year sentence.