|A screen grab from NBC4 Washington's report on the stabbing at Landmark carnival.|
The suspect is in custody and the victim and suspect know each other, NBC4 Washington reports. Fairfax County police responded to the scene with a helicopter due to the size of the crowd..
The Reithoffer Carnival was supposed to be open until 11 p.m., but was closed after the incident, and hundreds of people were forced to leave early.
Police spokesperson Crystal Nosal said small groups of males in their teens and 20s were fighting, the Washington Post states. Three people were taken into custody and one was charged with felonious assault, Nosal said. The carnival is to run there through April 17.