'Drunk mother passed out on baby son, smothering him to death'

A mother has been charged with manslaughter after she passed out drunk, falling asleep and smothering her 13-month-old son to death, according to police.

Antoinette King was charged on Monday for allegedly suffocating her baby boy Jeremiah under her body weight on January 18 in New Jersey.

The 33-year-old told investigators she drank four "airplane" bottles of alcohol, took an opioid-based prescription pill and headed to her mother's home.

Two hours later ambulance and police were called after King's mother found her daughter and grandson unconscious at her home.

According to a police statement, King said she drank the alcohol and consumed the pill then took a taxi "to attempt to hang out with friends" at a hotel.

Both mother and child were unresponsive when emergency responders arrived, though King was later revived with the use of Narcan, a drug that reverses the effect of opioid overdoses, the prosecutor's office said.

An autopsy later showed Jeremiah died of asphyxiation after he was unable to breathe under the weight of his mother's body.

King originally was charged with endangering the welfare of a child, but the charge was upgraded to manslaughter after blood tests showed that she had been intoxicated.