Alexander Draper, 14, is with 49-year-old Jerri Gray, who faces a charge of violating a custody order, police said.

The teen is considered to be at a 'stage of critical health risk', but authorities could not provide details about his medical condition beyond his weight, said Greenville County Sheriff's Lieutenant Shea Smith.

The state Department of Social Services contacted deputies Tuesday after Gray failed to make a scheduled court appearance so officials could begin investigating claims of child neglect and endangerment.

'We urgently hope that his mother will bring him back, or law enforcement will find him, so he can get the care he needs,' DSS spokesman Marilyn Matheus said in a statement.

The agency doesn't get involved in such cases based on a child's weight alone, but will take action in 'cases where health care professionals believe a child is at risk of harm because a parent is neglecting to provide necessary medical care,' Ms Matheus wrote.

A judge ordered the teen taken into protective custody.

Ms Gray and Mr Draper were last seen on Monday at their home in Travellers Rest, north of Greenville. -- AP