Police have charged a 38-year-old woman with murder in connection with the deaths of her 12-year-old daughter and 13-year-old son.

As she was hospitalised at Queen Elizabeth Hospital, the court proceedings began today at Tuen Mun Magistrates' Courts in her absence.

The woman and her two children were found lying unconscious inside a bedroom in their home at Tuen Mun's Greenland Garden on Wednesday.

The children were certified dead at the scene. An autopsy showed they died of carbon monoxide inhalation.