The New Jersey mother who was found in her car on the side of the road as both her children were "bound and restrained" in the back seat was formally charged on Wednesday, officials said.
Yuhwei Chou was charged with two counts of murder during her court appearance via video conference, the Somerset County Prosecutor's Office said. Chou is next expected to be in court next week for a bail detention hearing, the prosecutor's office said.
Police were called just after 7:30 a.m. Tuesday about a disabled vehicle on the side of Mountain View Road in Hillsborough, according to Somerset County Prosecutor Michael Robertson. In a booster seat in the back was 7-year-old Samantha Ross, while 10-month-old Paul Ross was in a baby seat next to her, the prosecutor's office said.
Both children, the daughter and son of 36-year-old Chou, were bound and restrained in their seats, officers said, and not breathing. They were pronounced dead at the scene. Law enforcement sources said the kids appeared to have suffocated.
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A second source with direct knowledge of the investigation confirmed to NBC New York that at least one of the children — possibly both — was bound with duct tape over their eyes and mouth. There were no obvious injuries or wounds seen initially on the children's bodies, the source said.
The medical examiner has yet to conduct an autopsy to make an official ruling on the cause of death.
While detectives look into the events that caused the deaths of the young children, the investigation has shown that Chou was responsible for their deaths, the county prosecutor said. A motive has not yet been released.
Samantha was a student at the private Waldorf School of Princeton, and previously attended Orchard Hill Elementary School, according to a police source.
A source who was part of the investigation said that there were domestic issues between Chou and her husband, who was at work at the time the vehicle and children were discovered.
Robertson said that anyone with information regarding the deaths of the children should contact the major crimes unit at the Somerset County Prosecutor's Office or Hillsborough Township police.