INDIANAPOLIS -- An acquaintance of Desmond Turner, who is on trial in the slayings of seven people during a botched robbery attempt, testified Tuesday that Turner told him he planned to rob "the Mexicans down the street" just moments before the killings.

Robert Swartz, who lives down the street from the home in which members of the Covarrubias and Valdez families were killed on June 1, 2006, said Turner offered to give him marijuana in exchange for duct tape so he could "hit a lick" -- street slang for commit a robbery -- on the day of the slayings.

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Swartz, who works in the heating and cooling business, testified that he told Turner that he didn't have duct tape, but said "he thought I was lying."

Swartz also testified that he called his aunt when he learned of the slayings and told her, "I think I know who done it."

Victims' family members erupted in tears as they listened to Swartz's testimony through a translator.

Earlier in the morning, Harrold James Couch, 50, testified in Marion Criminal Court that Turner, 31, called him in the days before the June 1, 2006, slayings to ask where he could get a high-powered rifle.

Security was tightened in the second day of testimony. Turner could be sentenced to life imprisonment if a judge finds him guilty of all seven killings. His mother and a few other supporters were in the courtroom, as were relatives of those slain.

Prosecutor Carl Brizzi said his team intends to call between 80 to 100 witnesses over the next two weeks and that testimony is key to the case because he lacks DNA evidence to tie Turner to the slayings.

"It's a puzzle of what I would say is very compelling circumstantial evidence," Brizzi said Tuesday. "As I stated in the opening statement, no physical evidence, no DNA, no blood, no blood in the getaway truck, no murder weapons, no fingerprints, so that's the reason why … we have to bring in so many witnesses to create a compelling circumstantial case."

The defense said it plans to call as many as 60 witnesses.

Prosecutors said Turner shot four adults and three children while looking for a safe full of money and drugs in an eastside home. There was no such safe.

Defense attorneys maintain that Turner wasn't involved in the crime. In opening statements, Turner's attorneys argued that shoe prints found at the scene don’t match, and that other people in the neighborhood had ill will toward the family.

Judge Robert Altice will decide Turner's innocence or guilt. Prosecutors had been seeking the death penalty for Turner until last month, when they announced a deal to drop it in exchange for Turner waiving his right to a jury trial.

6News will be updating this story from court, so check back frequently for updates and follow theindychannel on Twitter.