Apparently a Braves fan got into a scuffle with an usher in the 8th and bit him.
The Nats should have several Metropolitan Police officers at the park, the way the NYPD patrols Yankee Stadium. In The Bronx, stewards are the first line, telling fans to behave. If the fans don't, the steward waves down a couple of police, real police and not rent-a-cops. And that's the end of trouble, and troublemakers.
This
Braves fan should be in jail.
Correction by Jesse D in tweet: not a Braves fan. Was yelling obscenities at Marcell Ozuna, and both Braves and Nats fans complained. Fan was arrested (good!) and taken to jail (great!)