"Non-stop shouting" was heard coming from Blade Runner Oscar Pistorius' home before his girlfriend was shot dead, his bail hearing was told.
Prosecutor Gerrie Nel said the prosecution team has a witness who heard the shouting between 2am and 3am.
The details were revealed as the second day of the 26-year-old athlete's bail hearing began at Pretoria Magistrates' Court.
In an affidavit, Paralympic star Pistorius has denied murdering the model Reeva Steenkamp, 29, at his home in the early hours of Thursday.
He has said the couple were in love and he fired through his closed bathroom door, hitting the victim, thinking a burglar or burglars were inside.
Steenkamp was hit three times and the court heard the bullets hit her arm, hip and head.
Pistorius has said he shot her with a 9mm pistol.
An unlicensed .38 handgun was found at the property in the exclusive Silver Lakes Golf Estate.
Investigating officer Hilton Botha said he wanted the Olympian charged additionally with possession of an illegal weapon and ammunition.