** UPDATED 11 a.m. with MPD arresting an 18-year-old man in connection with the shooting, additional details. **​

Police arrested an 18-year-old man overnight for allegedly shooting his half-brother by accident aboard a Metro Red Line train.

Jermaine Brown, 18, of Seat Pleasant, Md., was taken into custody by Metro Transit Police Department officers at a motel in Capitol Heights, Md., shortly before midnight Sunday. The suspect is currently charged with a single count of first-degree assault in Montgomery County.

The shooting occurred about 3 p.m. Monday aboard the train as it arrived at the Takoma Metrorail Station. Brown was traveling with his 14-year-old half-brother when there was an altercation aboard the train involving Brown and three other individuals. During the fight, which was captured by digital video cameras aboard the railcar, Brown allegedly pulled a gun and fired multiple times. One round struck Brown’s half-brother in the abdomen, while two other bullets struck the railcar, the MTPD said.

As of Sunday evening, the teen remained hospitalized in stable condition, police said. Trains were forced to single-track for several hours while police and paramedics treated the teen and investigated the site.

People with information about the shooting or the three individuals are encouraged to call 911 or MTP at 202-962-2121.