07/03/2014 08:09 GMT | Updated 07/03/2014 08:59 GMT

Ex-Girlfriend Recalls: 'He Cheated On Me With Reeva'

An ex-girlfriend has given a damning testimony concerning the character of Oscar Pistorius during his murder trial today.

Samantha Taylor who dated the star in 2010, testified in court that she had witnessed the blade runner fire his gun through the open sunroof of his car after becoming "irritated" when they were stopped by police.

She said: "Oscar and Darren were pretty anxious and irritated at the policeman. They laughed and they said that they wanted to shoot a robot (traffic light) and then Oscar shot a bullet out the sunroof."

As well as the murder of supermodel Reeva Steenkamp, the South African sprinter also stands accused of several counts of firearm charges, including firing a pistol through the sunroof of a car.

Ms Taylor went on to testify the gold medallist "always" carried a gun with him, except when he slept when it was next to the bed with his prosthetic legs.

Addressing the judge, Ms Taylor recalled during the term of their relationship that Pistorius had shouted her several times and claims to have witnessed the accused shout at many people during their relationship, including her sister, her best friend and his best friend.

Taylor, who was 17 at the time of her relationship with the star, went on to cast doubt on the defence's argument that the high pitched screams, outlined in the testimonies of other witnesses, could not have been Oscar's, saying: "He does not scream like a woman."

In an attempt to differentiate between screams of anger and of fear, Barry Roux, the defence counsel, asked Taylor: "Have you ever heard Mr Pistorius scream when his life was threatened?" To which she stated she had not.

Ms Taylor broke down in tears as she recalled the end of their relationship, saying: "He cheated on me with Reeva."

She later recounted that their relationship ended when Pistorius took Reeva to the sports awards on 4 November 2012, saying: "We had not officially broken up at that time."

She added: "Over that week there was a lot of commotion in our relationship.

"We were still together but we were having problems."

The trial continues.