Cosmo DiNardo and Sean Kratz, cousins in Pennsylvania accused in the deaths of multiple men in July, pleaded not guilty at an arraignment hearing on Thursday. The move reportedly puts the option of the death penalty back on the table for prosecutors, who previously arranged a plea deal for DiNardo if he pleaded guilty.

DiNardo, who’s charged in four deaths, and Sean Kratz, who’s charged in three, both pleaded not guilty to multiple charges of murder and corpse abuse.

In July, DiNardo admitted to killing the four missing men and told investigators where they could find the bodies. In exchange, prosecutors agreed to take the death penalty off the table.

On Wednesday, prosecutors filed notices of aggravating circumstances in the case, essentially allowing them to pursue the death penalty if the cousins are convicted, Fox 29 reported. The district attorney’s office told the outlet that the filing was normal and would not interfere with DiNardo’s plea deal, assuming he pleaded guilty.

PROSECUTORS MOVE TO KEEP DEATH PENALTY AN OPTION IN SLAYING

"We made an agreement with Cosmo DiNardo,” Bucks County District Attorney Matthew Weintraub told reporters. “We're the district attorney's office: We honor our agreements. So should Mr. DiNardo decide to uphold his end of the bargain, we will not seek the death penalty against him."

Kratz's lawyer, Niels C. Eriksen Jr., said he commended the district attorney for extending to DiNardo an offer that removes the death penalty as punishment but was "disappointed and confused by today's action of certifying Mr. Kratz's case for capital punishment."

"DiNardo is the admitted killer," he said. "We look forward to challenging the evidence and the aggravators at the appropriate time."

Kratz gave authorities conflicting stories in July when he was interviewed about the missing men. He claimed that he had not participated in the slayings and vomited after the first man was shot, according to Detective Martin McDonough.

DETECTIVE: COUSINS WENT FOR CHEESESTEAKS AFTER 4 MEN KILLED

“He initially thought that he could talk his way out of his involvement here,” McDonough said.

The disappearances of Mark Sturgis, Tom Meo, Dean Finocchiaro and Jimi Taro Patrick over the summer sparked an exhaustive manhunt on a 90-acre farm owned by DiNardo's parents in Solebury, 30 miles north of Philadelphia. The victims ranged in age from 19 to 22.

Police used cadaver dogs and heavy construction equipment and brought in dozens of officers from the region to assist in the search until they finally found three of the men buried in an oil tank about 12-feet in the ground.

DiNardo told police that he crushed one of the men with a backhoe after shooting him and tried to set three of the bodies on fire before burying them in the metal container, court documents show. He also told authorities that he lured the men to the farm under the assumption he was going to sell them marijuana.

The Associated Press contributed to this report.