A six-year-old boy has shot and gravely wounded a teacher at an elementary school in the southern US state of Virginia.

The shooting occurred in the city of Newport News at around 2 p.m. on Friday.

Police said the boy fired one shot at a teacher, a woman in her 30s, in a first-grade classroom. She suffered life-threatening injuries.

The boy was taken into custody. There are no reports of student injuries.

A woman who came to pick up her son at the school after the incident said her heart stopped when she learned the news. She said she panicked fearing that her son may have been the one person who was shot.

Police said, "This was not an accidental shooting." Investigators are trying to figure out where the boy obtained the handgun.