09/19/2012 07:26 pm ET Updated Sep 20, 2012

D.C. School Shooting: Coolidge High School Student Shot By Fellow Student On School Grounds, Police Say

WASHINGTON -- An 18-year-old student at Coolidge High School in Northwest D.C. was shot on school property by a fellow student on Wednesday, just after 3:15 p.m., police said.

NBC4 reports that the victim was shot in the leg, and was conscious and breathing when authorities arrived. He was taken to the hospital with non-life threatening injuries. The shooter, found near the school shortly afterward, was taken into custody, according to WJLA/ABC7. Neither teen's name was released.

The school was placed on lockdown after the shooting.

WTOP, quoting D.C. police, reported that the two students had "argued verbally earlier in the day:"

After that argument, authorities say one student left the building and then came back after school, when the shooting occurred on school grounds.

D.C. schools chancellor Kaya Henderson told WJLA that the shooting is "troubling," but appeared to be an isolated incident. Henderson also that the gun doesn't appear to have been brought inside the school. Counselors and extra staff will be at the school on Thursday, Henderson said.