Gabriela Guevara, 24, helped lift and dump the body of her boyfriend's mother, according to authorities
Credit: Omaha Police

Testimony has put a tighter focus on the role of a girlfriend accused of aiding a Nebraska man, Roberto C. Martinez-Marinero, who is charged with murder for stabbing his mother, throwing his 4-year-old half-brother to his death from a bridge into a river and tossing his 11-month old baby brother into a dumpster.

Gabriela Guevara, 24, helped Martinez-Marinero lift the body of Jesus Ismenia Marinero, 45, into a car, pushing her feet as he pulled her arms, according to video captured by a neighbor’s security camera, said Omaha Police detective Wendi Dye in court Friday, the World-Herald reports.

Guevara – who has denied any involvement – then assisted Martinez-Marinero in dumping Ismenia, as she was known by friends and family, and who may have been alive when her son and his girlfriend disposed of her in a ditch on May 5 or early May 6, the detective said.

Pending a final autopsy, prosecutors said Guevara could be charged with murder if it’s determined that Ismenia Marinero died after being dumped.

Martinez-Marineroa, 25, already faces first-degree murder charges for the deaths of his mother and half brother, Josue Ramirez-Marinero, whose body was recovered from the Elkhorn River.

For now Guevara stands accused of five felony counts of accessory, including two of being an accessory to murder, after – according to Dye – Guevara was on hand when Martinez-Marinero threw Josue into the river and tossed 11-month-old Angel Ramirez-Marinero, into a dumpster.

The discovery of Angel, who was overheard rustling by a passerby and has since recovered, and the search for Josue after their mother’s body was found eventually led Martinez-Marinero to walk into the Douglas County Department of Corrections, where he “advised staff that he was involved in the death of his mother” and was arrested, the prosecutor said.

Relatives of the family told PEOPLE that Ismenia Marinero, one of nine children and the mother of seven, longed for a better life for her family in the United States after leaving El Salvador in 1999. Only Roberto followed her.

She settled in Omaha in 2003 after hearing about jobs in the meatpacking plants, and gave birth to Josue and Angel. But in the last weeks of her life she struggled as her house was broken into and set on fire, and was living with a sister, Reina Rosa. Relatives encouraged her to move out of state, but fearing that Roberto might be involved in trouble, “she said no, she couldn’t leave Roberto here,” Reina told PEOPLE. “She thought that in some ways she would protect him.”

Mother and son had argued about money in the weeks prior to the killings, and broke into an argument again at Roberto’s house when Roberto stabbed Ismenia Marinero using a six-inch blade and beat her with an aluminum baseball bat, Dye said in court.

He remains in custody, as does Guevara. Following Friday’s testimony, a judge upped Guevara’s bail from $1 million to $5 million. Guevara has plead not guilty to the charges.

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