Amanda Thomas, the assistant manager of the Patee gas station at 2260 Lumpkin Road, sensed that something was wrong when Jeannette Michelle Hawes, a regular customer, walked into the store Thursday afternoon with her 1-year-old son and 3-year-old daughter.

"She looked very distraught," Ms. Thomas said. "I asked her if she was OK."

Ms. Thomas said she saw Ms. Hawes take the children into the bathroom, and moments later "I heard the kids cry. Then heard a different sound -- very undescribable," she said.

After Ms. Thomas and three customers tried to unlock the bathroom door, she said, she called 911.

Upon arrival at the store, Richmond County deputies pried open the locked door with a screwdriver and found Ms. Hawes lying on the floor with her two children.

The mother, who Ms. Thomas said was an aspiring model, still had a black steak knife in her possession. The weapon was covered with blood, police said.

Ms. Hawes, 22, was charged Thursday with two counts of murder and possession of a knife during the commission of a crime.

Shakayla Hawes, 3, and Jordon Hawes, 1, were pronounced dead at Medical College of Georgia Hospital at 3:30 p.m. by Richmond County Chief Deputy Coroner Mark Bowen.

Both children died of multiple stab wounds to the chest, Deputy Bowen said.

"You think you've seen the worst, but sometimes you still see something that tops it," he said. "It's probably one of the hardest cases I've ever worked."

Wanda Barton, who lives next to the food mart in the Fairway Village Apartments, said she rushed to the scene in time to see Ms. Hawes being taken away by police.

"She wasn't crying or showing any emotion," Ms. Barton said.

Shelia Langston, who also lives in the apartments, said she just kept thinking of her own 7-year-old child.

"It don't make sense," Ms. Langston said.

Staff Writer Adam Folk contributed to this article.