INDIANAPOLIS -- The prosecution's star witness in the Desmond Turner trial testified Thursday morning that he saw Turner holding an assault rifle while on the porch of the home in which seven people were slain in 2006.

The testimony from Brandon Griffith (pictured) came on the fourth day of testimony in the murder trial in the city's largest mass slaying and marked the first time a witness directly placed Turner at the scene at the time the crime was committed.

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During morning testimony, the prosecution called two witnesses to corroborate previous testimony provided by those who knew Turner and/or the Valdez and Covarrubias families at the time of the killings on June 1, 2006, Call 6's Rafael Sanchez reported.

Griffith mumbled at times while on the stand, but testified that Turner told him he wanted to "hit a lick," a street term for commit a robbery, on the Covarrubias and Valdez families because he thought they had money, citing the type of cars they drove.

"It's our belief that he (Turner) was the one, and the evidence so far has been … that Brandon was telling the defendant that the Mexican family had money, that they were drug dealers, that sort of thing," said Marion County Prosecutor Carl Brizzi.

In his testimony, Griffith also said that he and Turner talked about a possible plot to kidnap Luis Albarran, a 5-year-old who was living in the home, while he played on a trampoline in an effort to extort money from the family.

Griffith said Turner tried to obtain duct tape, and offered to trade a half-pound of marijuana in exchange for tape.

Griffith testified that he changed his statements to police three times because he feared that if he spoke, Turner would kill him.

"You have somebody (Turner) that's not right in their mind, and that's sick," said Mario Albarran, son of one of the victims. "That's all I can say. He's one sick person."

Also in Thursday morning's testimony, Ricky Gilreath backed up witness testimony earlier in the week that indicated two men were seen near the Hamilton Avenue home just before its occupants were killed.

Gilreath testified that Griffith told him "something about to go down" on the day of the shootings.

Gilreath said that one of the men appeared to have an assault rifle and that he watched as "they kind of hesitated, then stepped in."

In his testimony, Gilreath said he saw one of the victims, Flora Albarran, enter the house. "She tried to step back out, but was pulled in," he said. "Then, there was a scream."

Gilreath said he heard shots, then watched the men run out of the house.

Prosecutors don't have DNA evidence in the case, so they hope to build an insurmountable case upon circumstantial evidence.

Defense attorneys have attempted to poke holes in prosecution witness testimony by questioning their accounts of the events.

Prosecutors had sought the death penalty until last month, when they announced a deal to drop that in exchange for Turner waiving his right to a jury trial.

As many as 160 witnesses could be called to the trial, which is expected to last two weeks.

6News is sending updates regarding developments in the courtroom throughout the trial. See those updates here, and follow us on Twitter.