Marion County Prosecutor Carl Brizzi declared Desmond Turner a killer and took account of the carnage spread among seven victims inside a house on Hamilton Avenue.

But his momentum at the start of Turner’s murder trial Monday was overwhelmed when he got to the child victims: three boys found on a bed with the television still flickering, 13 gunshots among them. Eight gunshots alone suffered by 8-year-old David Covarrubias.

“Eight?” said a voice from the gallery, interrupting him.

Brizzi paused. “Eight,” he repeated, his voice cracking.

Gasps at gruesome details punctuated the first day of a trial — expected to last two weeks — in the June 2006 slayings that also included four adults on Indianapolis’ Near Eastside.

“I remember having to take a deep breath,” vice officer Tabitha Forehand said about seeing the children in the back bedroom. “It was the saddest thing I’ve ever seen in my life.”

She recalled an impromptu rite performed near the children by officer Michael Kermon, the first officer inside the house. “He said a prayer in Spanish and did the sign of the cross.”

Killed in the shooting were Emma Valdez, 46, and her partner, Alberto Covarrubias, 56; their two young children; Valdez’s adult son and daughter; and her 5-year-old grandson.

Turner, 31, and his alleged accomplice, James Stewart, 33, each face about two dozen charges, including murder and robbery. Brizzi is seeking a life sentence without parole for Turner; Stewart’s trial is set for Dec. 7.

Turner maintains his innocence, and his attorneys began building a case Monday that prosecutors had charged the wrong man after relying on witnesses with a grudge against the victims. The defense cited a feud between Valdez’s surviving adult son, Mario Albarran, and members of another family on the block, a rivalry rooted in a love triangle and charges of snitching to police.

“There were other people in that neighborhood . . . that wanted the Valdez-Covarrubias family gone,” defense attorney Lorinda Youngcourt said.

Brizzi acknowledged the lack of DNA, fingerprints, weapons or eyewitness identifications placing Turner in the house, but he said other evidence should overcome any doubts.

Witnesses are expected to testify that Turner talked just before the killings of “hitting a lick,” or a robbery, at “the Mexican house.” The next morning, Turner fled to Kentucky after he had become a suspect, and police found his jeans and T-shirt soaking in a bathtub at a friend’s house.

“An innocent family was slaughtered,” Brizzi said, because Turner was hoping to steal a rumored cache of drugs and money that didn’t exist.

Today’s testimony could address what led police to suspect Turner within hours of the shootings, and prosecutors also could begin calling crime lab specialists who processed evidence.

Marion Superior Court Judge Robert Altice alone will decide Turner’s guilt. Last month, Turner waived his right to a jury in exchange for Brizzi dropping a death penalty request.

Altice already had seen grisly crime-scene photos that were displayed in the courtroom Monday. A monitor is angled so the gallery — divided among the victims’ family and friends, supporters of the defendant and the media — can’t see the photos.

But the testimony was descriptive enough, particularly when Kermon testified about finding the children’s maimed bodies.

“It’s really hard being in there,” said Esmeralda Espinoza, 19, Valdez’s niece, adding that each detail reinforces her belief the death penalty is merited. “I don’t know how anybody can do that.”

Across the gallery, Turner’s mother, Brenda Baymon, sat with a handful of family members — listening, she said, and praying. She believes in her son’s innocence, she said, in part because he has always seemed to love children; he has a 7-year-old son.

“I pray to leave this in God’s hands,” Baymon said, “and to ask him to strengthen me for the outcome. I also ask him to let me be around my child again.”