A 15-year-old teen was beaten and robbed at a subway platform in Brooklyn on Friday.

Police say the teen was jumped by another group of teens after he got onto the Brooklyn-bound L train at the Broadway Junction station around 3:30 p.m. yesterday. The fight spilled out onto the platform at the next stop at the elevated Atlantic Avenue station. The News has video of the assault.

The attackers stole the teen's pants, shoes, and phone. The victim was taken to Brookdale University Hospital with injuries to his head and body. Cops say no arrests have been made yet, but the investigation is ongoing.

Community activist Tony Herbert told the News that this is just the latest example of escalating gang violence between teens: "What is happening nowadays is a group of teens will walk up to another group of teens, whether they be two or more, and ask what gang they reppin, then in a flash of a second the assault begins," he said.

In an email, Herbert pointed to another recent incident, a video showing police officers attempting to arrest teens at the 125th Street station for fare beating only to be assaulted and attacked themselves by friends of the teens.

"Resisting arrest is truly the pinnacle of most of these arrest going bad, this is alarming," Herbert said in a statement about that incident. "In as much we are in the days of tense police and community relations, citizens of NYC are obligated to follow the law even if some feel others aren't doing so, and the continued actions of others as displayed by these girls in this video will only lead to something even worse when law enforcement officers are placed in a position to defend themselves from angry groups. Thankfully these officers did show great restraint."