Two children found dead under an apartment sink were bathed and dressed by their mother before being wrapped in trash bags, according to arrest warrants released Wednesday.

The warrants provide new details of the events that police say led to the arrest of a troubled single mother suspected of leaving her children in a hot car for hours while she was at work.

Sametta Heyward, 27, was charged Tuesday with homicide by child abuse after the bodies of 1-year-old Triniti Campbell and 4-year-old Shawn Campbell Jr. were found in her apartment.

The warrants said Heyward called her ex-boyfriend and told him she had "killed her babies."

Authorities have not determined exactly how the children died. Heyward had left them in a car on Sunday as temperatures outside reached 88 degrees, the warrants said.

Heyward was being held at a Berkeley County jail. Her attorney said he didn't know when he would ask for a bail hearing.