A man is in custody after a half-day SWAT standoff at a downtown Atlanta residence.

Police were called to 379 St. John's Avenue around 9 am Thursday, when the father of the gunman said his son was armed and threatening to harm his family and himself.

The suspect was taken into custody shortly before 2 pm.

Police said the man, who has only been identified as a 24-year-old, may have a history of mental health issues.

This story is developing.

IMAGES: Thursday's SWAT standoff