'I'm scared to sleep', tearful Pistorius tells court

Oscar Pistorius becomes emotional during his trial at the high court in Pretoria April 7, 2014. [Photo/Agencies]

"Exhausted"

All about Pistorius

His defence hinges on his assertion, made under oath at his bail hearing, that he mistook Steenkamp for an intruder hiding in the toilet and opened fire.

However, witnesses living close to Pistorius' home in a gated Pretoria community have testified to hearing the terrified screams of a woman before and during a volley of shots in the early hours of Feb 14, 2013.

South Africa's firearms and self-defence laws make clear a person may only shoot if there is a direct threat to somebody's life - regulations Pistorius acknowledged in a written gun-licence test presented by the prosecution.

Ashen-faced, Pistorius said he had not slept the night before his testimony, leading Judge Thokozile Masipa to adjourn the session early after little more than an hour of cross-examination.

"He does look exhausted," Masipa said. "He does sound exhausted." As he stepped from the witness box, Pistorius slumped into the outstretched arms of his sister Aimee.

The trial resumes at 0730 GMT on Tuesday.

Pistorius takes stand in own defence at murder trial	Pistorius vomits at Steenkamp autopsy details in court	'Bloodcurdling' screams heard in Pistorius' home