Sean Kratz rejects plea deal of 59-118 years in jail. Case will now go to trial. Prosecution will seek death penalty. — Walter Perez (@WalterPerez6abc) May 16, 2018

Cosmo DiNardo and Sean Kratz

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DOYLESTOWN, Pa. (WPVI) -- Two cousins accused of killing together could find themselves pitted against one other in court after one took a plea deal Wednesday and the other rejected one in the gruesome deaths of four young men found buried last summer on a suburban Philadelphia farm.Prosecutors vowed to seek the death penalty against Sean Kratz after the 21-year-old stunned prosecutors, victims' families and even his own lawyer in turning down an offer that would have put him in prison for at least 59 years."Unexpected outcome," said Kratz's lawyer, Craig Penglase.Cosmo DiNardo, the cousin who earlier in the day pleaded guilty to four counts of murder in exchange for a life sentence, could be forced to testify at Kratz's trial, District Attorney Matthew Weintraub said.No trial date has been set. Prosecutors will seek the death penalty."I feel just as whipsawed, probably as many of you who are watching, as many of you who have questions," said Weintraub.The D.A. said he even spoke with Kratz privately to try to get him to change his mind. Now, Kratz case moves to trial and Weintraub will seek the death penalty."We're undaunted though as we continue to seek justice for our four boys, for Dean, for Jimmy, for John, for Mark," he said.DiNardo's guilty plea, which will put him behind bars for life, gave solace to a grieving father who turned to the stone-faced killer in a packed courtroom and said, "Your only way out of prison is wearing a toe tag.""That's the least we all deserve," said Mark Potash, the father of 22-year-old victim Mark Sturgis.Melissa Fratanduono, the mother of 21-year-old victim Tom Meo, cursed at DiNardo, saying it has "taken everything" for her not to kill him herself.DiNardo pleaded guilty to charges including first-degree murder, conspiracy, robbery and abuse of a corpse. His lawyer said he did so to avoid the death penalty.DiNardo was legally barred from possessing firearms due to an involuntary commitment. He had a schizophrenia diagnosis and repeated contacts with police, but lawyer Fortunato Perri said mental health professionals who evaluated DiNardo after his arrest weren't sure they could present an insanity defense.Police found the men after a grueling, five-day search.Three were lit on fire and placed 12-feet deep in an oil tank converted into a pig roaster.DiNardo allegedly lured them to his family's 90-acre farm under the guise of making marijuana deals.Jimi Taro Patrick's grandparents, who had raised the slain 19-year-old since birth, asked DiNardo to pray for them and his mother, who has severe mental illness.Someday, perhaps, they'll be able to forgive him, Sharon Patrick said."My heart is broken, and I will never, ever be the same," she said. "I love you Jimi and I miss him very, very much."The other victims were 19-year-old Dean Finocchiaro and 21-year-old Tom Meo.The families of the slain men are suing DiNardo's parents, saying they knew he had mental health issues and violent tendencies but didn't prevent him from accessing a gun.DiNardo's parents own the farm property in Solebury and construction and concrete companies in Bensalem, where they live.In his confession, DiNardo acknowledged selling handguns to local residents. Five months before the killings, police charged him with having a shotgun.------