A Colorado man has been jailed for the 2016 murder of his girlfriend aboard a train traveling from Wisconsin to Denver.
The Denver District Attorney’s Office said that Angelo Valentino Mantych, 41, was charged with first degree murder in the death of Marina Placensia, 28, KMGH reported.
Mantych, Placensia, and her four young children — three of them with Mantych as the father — boarded an Amtrak train in Racine, Wisconsin, on August 30, 2016, to travel to Denver. But when the train arrived at Denver’s Union Statio on September 1, Placensia was dead.
Mantych was reported to be on the station platform, an affidavit says, and he “appeared to be upset, crying and vomited several times.”
Mantych told police the family was moving to Denver. He said that about 20 minutes from their destination, he tried to awaken Placensia, but she didn’t respond.
The affidavit, however, says that police at the scene saw bruises on Placensia’s body that “appeared the be consistent with an assault or struggle. Mantych reportedly attributed the bruises to Placenia being “banged up while moving.”
The medical examiner later found found blunt trauma impacts on Placensia’s head, torso, and extremities.
On the same day Placensia was found dead aboard the train, her brother contacted police and told them that Mantych was abusive and should be considered a suspect in her death. A week alter, family acquaintances in Wisconsin told investigators that Mantych beat his girlfriend the day before they boarded the train. The witnesses said the couple fought often and that Mantych was physically and mentally abusive. One witness said Mantych beat her daily, and another said she had been hospitalized multiple times from his attacks.
Some of the witnesses said they suspected Mantych was abusing the children as well.
According to the affidavit, a friend of Placensia told detectives she had spoken with her family at moving back to Colorado to escape Mantych, but he overheard the call and told her “her would kill her if she left with the children.”
Some witnesses also said she wore long sleeves and sunglasses year-round to cover the bruises.
Police confirmed at least one arrest for Mantych in Racine. In 2016, he punch Placensia’s ear multiple times, causing her to lose her hearing in that ear.
The autopsy report found 35 internal and external injuries on Placensia’s body, but the medical examiner said they didn’t cause the death, which was listed as undetermined.
In May 2023, Dr. Bill Smock, a nationally recognized expert in asphyxia and suffocation, said he believed Placensia’s death was a result of asphyxia from suffocation. He declared her death to be a homicide, which the original medical examiner had not done, KDVR reported.
“Suffocation was the cause of Ms. Placensia’s homicidal death and occurred from the application of pressure to her face, obstruction of the nose and mouth, and created a hypoxic condition which led to her death,” that report says. ” … The manner of death is homicide.”
Mantych was arrested on October 30. Neither the police nor the district attorney’s office explained why it took seven years and an expert’s reexamination of the case to determine Placensia had been murdered.
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[Featured image: Angelo Mantych and Marina Placensia/Denver District Attorney’s Office]
