Updated

The mother of an infant found dead near the Sacramento River in Northern California has been charged with involuntary manslaughter and abusing or endangering the health of a child.

Yolo County District Attorney Jeff Reisig announced the charges against 23-year-old Samantha Green of Woodland as she faced her first court appearance Wednesday.

She was arrested Saturday in the death of 20-day-old Justice Rees.

'The charges also include an enhancement for inflicting great bodily injury on a child under age 5 during the commission of a felony.

The boy's body was found with no obvious signs of trauma last week in a swampy area. Sheriff's investigators say he may have died from drowning or hypothermia near the rural town of Knights Landing, about 30 miles west of Sacramento.