PRETORIA (AFP) - South African state prosecutor Gerrie Nel continued his fierce cross-examination of Oscar Pistorius on Thursday, claiming the sprinter was lying and that his account of events was "impossible."

Here are highlights from proceedings on the trial's 20th day:

- IMPOSSIBLE

State prosecutor Gerrie Nel said Pistorius's version of events that he woke up and moved the fans from his balcony into his bedroom was "impossible," disputing the athlete's assertion that police then moved the fans, duvet and curtains - key pieces of evidence - when they arrived at the crime scene.

"Your version is so improbable, that nobody would ever think it's reasonably, possibly true, it's so impossible," said Mr Nel.

- NO REASON

Pistorius agreed with Mr Nel when he said the athlete had no reason to shoot four times through a locked toilet door.

"We know for a fact there were no intruders in your house that night, we know for a fact there was no ladder against the wall," said Mr Nel.

"We know for a fact that you had no reason to shoot, objectively speaking." Pistorius replied, "that's correct, my lady."

- EGOTISTIC

Mr Nel said Pistorius was an egotistic boyfriend focused primarily on his own well-being and reputation, highlighting WhatsApp messages Ms Steenkamp sent to the athlete complaining about his controlling behaviour.

"Because it's all about Mr Pistorius, that is what your relationship was," said Mr Nel.

- SCARY

Pistorius says Ms Steenkamp wrote in a WhatsApps that she is scared of him because she had such deep emotions for him.

Pistorius denied "picking on" Ms Steenkamp, as she claimed in the same message.

- OFFENSIVE SONG

Pistorius said he didn't remember playing "Bitch don't kill my vibe," a rap song by Kendrick Lamar, in the car after him and Ms Steenkamp had a falling-out at a party.

"What song were you playing? Isn't it 'Bitch, don't kill my vibe?" asked Mr Nel. "I have no idea my lady," said Pistorius.

"If you put on a song, 'Bitch don't kill my vibe," said Mr Nel, his voice raising, "anyone would take offence to it."

- FINGER ON THE TRIGGER

Pistorius denied pulling the trigger of a Glock 27 handgun in Tasha's, an upmarket Johannesburg restaurant. He has pleaded not guilty to two charges of gun recklessness.

"As I said my lady I did not have my finger on the trigger," he said.

The athlete also denied shooting a gun out of a car's sunroof, saying that two state witnesses, Samantha Taylor, his ex-girlfriend, and Darren Fresco, a former friend, "fabricated" a story.

- RESPONSIBILITY

Mr Nel said repeatedly throughout the day that Pistorius avoids taking responsibility for his actions, a theme of his cross-examination.

"You see again Mr Pistorius, it's the strangest day today, you don't take responsibility for anything," said Mr Nel, after asking Pistorius about his gun habits.