Elisa Frank told police how Ahmad Otak, 21, murdered her sister Kimberley Frank, 17, and her friend Samantha Sykes, 18, in Wakefield. Her video testimony was played at Leeds Crown Court at the trial of Steven Harratt, who is accused of helping Otak to try and evade justice.
Miss Frank, then 19, said: “At one point he was standing more or less over her body and he spat on her body and started laughing.”
Otak then got her to ring her friend Samantha Sykes to tell her to come round. Before she got there Otak tied her hands and feet with electrical cables and he covered Kimberley’s body with a blanket.
Samantha was then attacked when she arrived at the flat complex.
Miss Frank’s said: “I just shouted come in, then there was a few seconds, after that there was just screaming.”
The court heard Otak untied Elisa and took her at knife-point to Harratt’s flat in Willow Grove, Sandal.
Harratt, 57, is also alleged to have provided Otak with £250, food, clothing and a satellite navigation system plus information about ferry crossings.
Otak planned to drive down to Dover and escape to France, but was apprehended by police in Kent.
Harratt pleads not guilty to assisting an offender.
The trial continues.