The two teenagers accused of killing Arun Kumar panicked after the blade they had intended to use as a scare tactic led to the Auckland dairy owner bleeding to death on the floor of his shop, a court has been told.
A picture of synthetic drug and cannabis use has also been painted in the hours before Mr Kumar was killed at the Railside Dairy on June 10 last year.
The teenagers' trial has entered its second week in the High Court at Auckland. A 14-year-old boy is charged with murder, while his 13-year-old co-accused faces a charge of manslaughter.
The pair, who have name suppression, also face counts of assault with intent to rob.
The jury has been played videos of two police interviews with a 14-year-old boy who followed the teens to the dairy and back to the older defendant's home as they fled.
Under cross examination by defence lawyer Maria Pecotic, the witness - whose name is suppressed due to his age - said the older accused was "terrified" when he returned home.
Ms Pecotic asked: "He said he thought he may have killed someone?"
The witness said: "Yes."
"He also said he honestly didn't expect that anyone would be hurt?" she said.
"Yes, that is correct," he replied.
The witness told the court the blade had been taken to the store as a scare tactic, rather than to hurt anyone.
He also spoke of scenes of panic when they returned to the 14-year-old accused's house.
"I saw blood on the door and I walked into [the defendant's] room and everyone was just panicking, everyone was shocked," the witness said.
The jury was told that the night before the incident, a group had been smoking "a little bit" of synthetic cannabis in the accused's bedroom.
The witness said he saw the younger boy smoking, and that it was possible the older boy was too.
He also said there was no discussion in the house about robbing a dairy and that the pair set out to rob West City Shoes.
The witness said he went along because he "just wanted to have a look".
The teens, who were aged 12 and 13 at the time of Mr Kumar's death, have pleaded not guilty to the charges.
Their lawyers say they lacked the "knowledge and intention" to commit the crimes.
The trial continues.